3 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
4 * 2004 Wim Taymans <wim.taymans@gmail.com>
6 * gstbin.c: GstBin container object and support code
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Library General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Library General Public License for more details.
18 * You should have received a copy of the GNU Library General Public
19 * License along with this library; if not, write to the
20 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
21 * Boston, MA 02110-1301, USA.
28 * @short_description: Base class and element that can contain other elements
30 * #GstBin is an element that can contain other #GstElement, allowing them to be
32 * Pads from the child elements can be ghosted to the bin, see #GstGhostPad.
33 * This makes the bin look like any other elements and enables creation of
34 * higher-level abstraction elements.
36 * A new #GstBin is created with gst_bin_new(). Use a #GstPipeline instead if you
37 * want to create a toplevel bin because a normal bin doesn't have a bus or
38 * handle clock distribution of its own.
40 * After the bin has been created you will typically add elements to it with
41 * gst_bin_add(). You can remove elements with gst_bin_remove().
43 * An element can be retrieved from a bin with gst_bin_get_by_name(), using the
44 * elements name. gst_bin_get_by_name_recurse_up() is mainly used for internal
45 * purposes and will query the parent bins when the element is not found in the
48 * An iterator of elements in a bin can be retrieved with
49 * gst_bin_iterate_elements(). Various other iterators exist to retrieve the
52 * gst_object_unref() is used to drop your reference to the bin.
54 * The #GstBin::element-added signal is fired whenever a new element is added to
55 * the bin. Likewise the #GstBin::element-removed signal is fired whenever an
56 * element is removed from the bin.
58 * <refsect2><title>Notes</title>
60 * A #GstBin internally intercepts every #GstMessage posted by its children and
61 * implements the following default behaviour for each of them:
64 * <term>GST_MESSAGE_EOS</term>
65 * <listitem><para>This message is only posted by sinks in the PLAYING
66 * state. If all sinks posted the EOS message, this bin will post and EOS
67 * message upwards.</para></listitem>
70 * <term>GST_MESSAGE_SEGMENT_START</term>
71 * <listitem><para>just collected and never forwarded upwards.
72 * The messages are used to decide when all elements have completed playback
73 * of their segment.</para></listitem>
76 * <term>GST_MESSAGE_SEGMENT_DONE</term>
77 * <listitem><para> Is posted by #GstBin when all elements that posted
78 * a SEGMENT_START have posted a SEGMENT_DONE.</para></listitem>
81 * <term>GST_MESSAGE_DURATION_CHANGED</term>
82 * <listitem><para> Is posted by an element that detected a change
83 * in the stream duration. The default bin behaviour is to clear any
84 * cached duration values so that the next duration query will perform
85 * a full duration recalculation. The duration change is posted to the
86 * application so that it can refetch the new duration with a duration
87 * query. Note that these messages can be posted before the bin is
88 * prerolled, in which case the duration query might fail.
92 * <term>GST_MESSAGE_CLOCK_LOST</term>
93 * <listitem><para> This message is posted by an element when it
94 * can no longer provide a clock. The default bin behaviour is to
95 * check if the lost clock was the one provided by the bin. If so and
96 * the bin is currently in the PLAYING state, the message is forwarded to
98 * This message is also generated when a clock provider is removed from
99 * the bin. If this message is received by the application, it should
100 * PAUSE the pipeline and set it back to PLAYING to force a new clock
105 * <term>GST_MESSAGE_CLOCK_PROVIDE</term>
106 * <listitem><para> This message is generated when an element
107 * can provide a clock. This mostly happens when a new clock
108 * provider is added to the bin. The default behaviour of the bin is to
109 * mark the currently selected clock as dirty, which will perform a clock
110 * recalculation the next time the bin is asked to provide a clock.
111 * This message is never sent tot the application but is forwarded to
112 * the parent of the bin.
116 * <term>OTHERS</term>
117 * <listitem><para> posted upwards.</para></listitem>
122 * A #GstBin implements the following default behaviour for answering to a
126 * <term>GST_QUERY_DURATION</term>
127 * <listitem><para>If the query has been asked before with the same format
128 * and the bin is a toplevel bin (ie. has no parent),
129 * use the cached previous value. If no previous value was cached, the
130 * query is sent to all sink elements in the bin and the MAXIMUM of all
131 * values is returned. If the bin is a toplevel bin the value is cached.
132 * If no sinks are available in the bin, the query fails.
136 * <term>GST_QUERY_POSITION</term>
137 * <listitem><para>The query is sent to all sink elements in the bin and the
138 * MAXIMUM of all values is returned. If no sinks are available in the bin,
143 * <term>OTHERS</term>
144 * <listitem><para>the query is forwarded to all sink elements, the result
145 * of the first sink that answers the query successfully is returned. If no
146 * sink is in the bin, the query fails.</para></listitem>
150 * A #GstBin will by default forward any event sent to it to all sink elements.
151 * If all the sinks return %TRUE, the bin will also return %TRUE, else %FALSE is
152 * returned. If no sinks are in the bin, the event handler will return %TRUE.
158 #include "gst_private.h"
160 #include "gstevent.h"
163 #include "gsterror.h"
165 #include "gstutils.h"
166 #include "gstchildproxy.h"
168 GST_DEBUG_CATEGORY_STATIC (bin_debug);
169 #define GST_CAT_DEFAULT bin_debug
171 /* a bin is toplevel if it has no parent or when it is configured to behave like
173 #define BIN_IS_TOPLEVEL(bin) ((GST_OBJECT_PARENT (bin) == NULL) || bin->priv->asynchandling)
175 #define GST_BIN_GET_PRIVATE(obj) \
176 (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_BIN, GstBinPrivate))
178 struct _GstBinPrivate
180 gboolean asynchandling;
181 /* if we get an ASYNC_DONE message from ourselves, this means that the
182 * subclass will simulate ASYNC behaviour without having ASYNC children. When
183 * such an ASYNC_DONE message is posted while we are doing a state change, we
184 * have to process the message after finishing the state change even when no
185 * child returned GST_STATE_CHANGE_ASYNC. */
186 gboolean pending_async_done;
188 guint32 structure_cookie;
195 /* forward messages from our children */
196 gboolean message_forward;
199 gboolean posted_playing;
208 static void gst_bin_dispose (GObject * object);
210 static void gst_bin_set_property (GObject * object, guint prop_id,
211 const GValue * value, GParamSpec * pspec);
212 static void gst_bin_get_property (GObject * object, guint prop_id,
213 GValue * value, GParamSpec * pspec);
215 static GstStateChangeReturn gst_bin_change_state_func (GstElement * element,
216 GstStateChange transition);
217 static gboolean gst_bin_post_message (GstElement * element, GstMessage * msg);
218 static GstStateChangeReturn gst_bin_get_state_func (GstElement * element,
219 GstState * state, GstState * pending, GstClockTime timeout);
220 static void bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
221 gboolean flag_pending, GstClockTime running_time);
222 static void bin_handle_async_start (GstBin * bin);
223 static void bin_push_state_continue (GstBin * bin, BinContinueData * data);
224 static void bin_do_eos (GstBin * bin);
226 static gboolean gst_bin_add_func (GstBin * bin, GstElement * element);
227 static gboolean gst_bin_remove_func (GstBin * bin, GstElement * element);
228 static void gst_bin_update_context (GstBin * bin, GstContext * context);
229 static void gst_bin_update_context_unlocked (GstBin * bin,
230 GstContext * context);
233 static void gst_bin_set_index_func (GstElement * element, GstIndex * index);
234 static GstIndex *gst_bin_get_index_func (GstElement * element);
237 static GstClock *gst_bin_provide_clock_func (GstElement * element);
238 static gboolean gst_bin_set_clock_func (GstElement * element, GstClock * clock);
240 static void gst_bin_handle_message_func (GstBin * bin, GstMessage * message);
241 static gboolean gst_bin_send_event (GstElement * element, GstEvent * event);
242 static GstBusSyncReply bin_bus_handler (GstBus * bus,
243 GstMessage * message, GstBin * bin);
244 static gboolean gst_bin_query (GstElement * element, GstQuery * query);
245 static void gst_bin_set_context (GstElement * element, GstContext * context);
247 static gboolean gst_bin_do_latency_func (GstBin * bin);
249 static void bin_remove_messages (GstBin * bin, GstObject * src,
250 GstMessageType types);
251 static void gst_bin_continue_func (GstBin * bin, BinContinueData * data);
252 static gint bin_element_is_sink (GstElement * child, GstBin * bin);
253 static gint bin_element_is_src (GstElement * child, GstBin * bin);
255 static GstIterator *gst_bin_sort_iterator_new (GstBin * bin);
257 /* Bin signals and properties */
266 #define DEFAULT_ASYNC_HANDLING FALSE
267 #define DEFAULT_MESSAGE_FORWARD FALSE
273 PROP_MESSAGE_FORWARD,
277 static void gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data);
279 static guint gst_bin_signals[LAST_SIGNAL] = { 0 };
283 static const GInterfaceInfo iface_info = { \
284 gst_bin_child_proxy_init, \
288 g_type_add_interface_static (g_define_type_id, GST_TYPE_CHILD_PROXY, &iface_info); \
290 GST_DEBUG_CATEGORY_INIT (bin_debug, "bin", GST_DEBUG_BOLD, \
291 "debugging info for the 'bin' container element"); \
295 #define gst_bin_parent_class parent_class
296 G_DEFINE_TYPE_WITH_CODE (GstBin, gst_bin, GST_TYPE_ELEMENT, _do_init);
299 gst_bin_child_proxy_get_child_by_index (GstChildProxy * child_proxy,
305 bin = GST_BIN_CAST (child_proxy);
307 GST_OBJECT_LOCK (bin);
308 if ((res = g_list_nth_data (bin->children, index)))
309 gst_object_ref (res);
310 GST_OBJECT_UNLOCK (bin);
312 return (GObject *) res;
316 gst_bin_child_proxy_get_children_count (GstChildProxy * child_proxy)
321 bin = GST_BIN_CAST (child_proxy);
323 GST_OBJECT_LOCK (bin);
324 num = bin->numchildren;
325 GST_OBJECT_UNLOCK (bin);
331 gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data)
333 GstChildProxyInterface *iface = g_iface;
335 iface->get_children_count = gst_bin_child_proxy_get_children_count;
336 iface->get_child_by_index = gst_bin_child_proxy_get_child_by_index;
340 _gst_boolean_accumulator (GSignalInvocationHint * ihint,
341 GValue * return_accu, const GValue * handler_return, gpointer dummy)
345 myboolean = g_value_get_boolean (handler_return);
346 if (!(ihint->run_type & G_SIGNAL_RUN_CLEANUP))
347 g_value_set_boolean (return_accu, myboolean);
349 GST_DEBUG ("invocation %d, %d", ihint->run_type, myboolean);
356 gst_bin_class_init (GstBinClass * klass)
358 GObjectClass *gobject_class;
359 GstElementClass *gstelement_class;
361 gobject_class = (GObjectClass *) klass;
362 gstelement_class = (GstElementClass *) klass;
364 g_type_class_add_private (klass, sizeof (GstBinPrivate));
366 gobject_class->set_property = gst_bin_set_property;
367 gobject_class->get_property = gst_bin_get_property;
370 * GstBin:async-handling:
372 * If set to %TRUE, the bin will handle asynchronous state changes.
373 * This should be used only if the bin subclass is modifying the state
374 * of its children on its own.
376 g_object_class_install_property (gobject_class, PROP_ASYNC_HANDLING,
377 g_param_spec_boolean ("async-handling", "Async Handling",
378 "The bin will handle Asynchronous state changes",
379 DEFAULT_ASYNC_HANDLING, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
382 * GstBin::element-added:
384 * @element: the #GstElement that was added to the bin
386 * Will be emitted after the element was added to the bin.
388 gst_bin_signals[ELEMENT_ADDED] =
389 g_signal_new ("element-added", G_TYPE_FROM_CLASS (klass),
390 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_added), NULL,
391 NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
393 * GstBin::element-removed:
395 * @element: the #GstElement that was removed from the bin
397 * Will be emitted after the element was removed from the bin.
399 gst_bin_signals[ELEMENT_REMOVED] =
400 g_signal_new ("element-removed", G_TYPE_FROM_CLASS (klass),
401 G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_removed), NULL,
402 NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
404 * GstBin::do-latency:
407 * Will be emitted when the bin needs to perform latency calculations. This
408 * signal is only emitted for toplevel bins or when async-handling is
411 * Only one signal handler is invoked. If no signals are connected, the
412 * default handler is invoked, which will query and distribute the lowest
413 * possible latency to all sinks.
415 * Connect to this signal if the default latency calculations are not
416 * sufficient, like when you need different latencies for different sinks in
419 gst_bin_signals[DO_LATENCY] =
420 g_signal_new ("do-latency", G_TYPE_FROM_CLASS (klass),
421 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstBinClass, do_latency),
422 _gst_boolean_accumulator, NULL, g_cclosure_marshal_generic,
423 G_TYPE_BOOLEAN, 0, G_TYPE_NONE);
426 * GstBin:message-forward:
428 * Forward all children messages, even those that would normally be filtered by
429 * the bin. This can be interesting when one wants to be notified of the EOS
430 * state of individual elements, for example.
432 * The messages are converted to an ELEMENT message with the bin as the
433 * source. The structure of the message is named 'GstBinForwarded' and contains
434 * a field named 'message' of type GST_TYPE_MESSAGE that contains the original
437 g_object_class_install_property (gobject_class, PROP_MESSAGE_FORWARD,
438 g_param_spec_boolean ("message-forward", "Message Forward",
439 "Forwards all children messages",
440 DEFAULT_MESSAGE_FORWARD, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
442 gobject_class->dispose = gst_bin_dispose;
444 gst_element_class_set_static_metadata (gstelement_class, "Generic bin",
446 "Simple container object",
447 "Erik Walthinsen <omega@cse.ogi.edu>,"
448 "Wim Taymans <wim.taymans@gmail.com>");
450 gstelement_class->change_state =
451 GST_DEBUG_FUNCPTR (gst_bin_change_state_func);
452 gstelement_class->post_message = GST_DEBUG_FUNCPTR (gst_bin_post_message);
453 gstelement_class->get_state = GST_DEBUG_FUNCPTR (gst_bin_get_state_func);
455 gstelement_class->get_index = GST_DEBUG_FUNCPTR (gst_bin_get_index_func);
456 gstelement_class->set_index = GST_DEBUG_FUNCPTR (gst_bin_set_index_func);
458 gstelement_class->provide_clock =
459 GST_DEBUG_FUNCPTR (gst_bin_provide_clock_func);
460 gstelement_class->set_clock = GST_DEBUG_FUNCPTR (gst_bin_set_clock_func);
462 gstelement_class->send_event = GST_DEBUG_FUNCPTR (gst_bin_send_event);
463 gstelement_class->query = GST_DEBUG_FUNCPTR (gst_bin_query);
464 gstelement_class->set_context = GST_DEBUG_FUNCPTR (gst_bin_set_context);
466 klass->add_element = GST_DEBUG_FUNCPTR (gst_bin_add_func);
467 klass->remove_element = GST_DEBUG_FUNCPTR (gst_bin_remove_func);
468 klass->handle_message = GST_DEBUG_FUNCPTR (gst_bin_handle_message_func);
470 klass->do_latency = GST_DEBUG_FUNCPTR (gst_bin_do_latency_func);
474 gst_bin_init (GstBin * bin)
478 bin->numchildren = 0;
479 bin->children = NULL;
480 bin->children_cookie = 0;
481 bin->messages = NULL;
482 bin->provided_clock = NULL;
483 bin->clock_dirty = FALSE;
485 /* Set up a bus for listening to child elements */
486 bus = g_object_new (GST_TYPE_BUS, "enable-async", FALSE, NULL);
487 bin->child_bus = bus;
488 GST_DEBUG_OBJECT (bin, "using bus %" GST_PTR_FORMAT " to listen to children",
490 gst_bus_set_sync_handler (bus, (GstBusSyncHandler) bin_bus_handler, bin,
493 bin->priv = GST_BIN_GET_PRIVATE (bin);
494 bin->priv->asynchandling = DEFAULT_ASYNC_HANDLING;
495 bin->priv->structure_cookie = 0;
496 bin->priv->message_forward = DEFAULT_MESSAGE_FORWARD;
500 gst_bin_dispose (GObject * object)
502 GstBin *bin = GST_BIN_CAST (object);
503 GstBus **child_bus_p = &bin->child_bus;
504 GstClock **provided_clock_p = &bin->provided_clock;
505 GstElement **clock_provider_p = &bin->clock_provider;
507 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, object, "%p dispose", object);
509 GST_OBJECT_LOCK (object);
510 gst_object_replace ((GstObject **) child_bus_p, NULL);
511 gst_object_replace ((GstObject **) provided_clock_p, NULL);
512 gst_object_replace ((GstObject **) clock_provider_p, NULL);
513 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
514 GST_OBJECT_UNLOCK (object);
516 while (bin->children) {
517 gst_bin_remove (bin, GST_ELEMENT_CAST (bin->children->data));
519 if (G_UNLIKELY (bin->children != NULL)) {
520 g_critical ("could not remove elements from bin '%s'",
521 GST_STR_NULL (GST_OBJECT_NAME (object)));
524 G_OBJECT_CLASS (parent_class)->dispose (object);
529 * @name: (allow-none): the name of the new bin
531 * Creates a new bin with the given name.
533 * Returns: (transfer floating): a new #GstBin
536 gst_bin_new (const gchar * name)
538 return gst_element_factory_make ("bin", name);
542 gst_bin_set_property (GObject * object, guint prop_id,
543 const GValue * value, GParamSpec * pspec)
547 gstbin = GST_BIN_CAST (object);
550 case PROP_ASYNC_HANDLING:
551 GST_OBJECT_LOCK (gstbin);
552 gstbin->priv->asynchandling = g_value_get_boolean (value);
553 GST_OBJECT_UNLOCK (gstbin);
555 case PROP_MESSAGE_FORWARD:
556 GST_OBJECT_LOCK (gstbin);
557 gstbin->priv->message_forward = g_value_get_boolean (value);
558 GST_OBJECT_UNLOCK (gstbin);
561 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
567 gst_bin_get_property (GObject * object, guint prop_id,
568 GValue * value, GParamSpec * pspec)
572 gstbin = GST_BIN_CAST (object);
575 case PROP_ASYNC_HANDLING:
576 GST_OBJECT_LOCK (gstbin);
577 g_value_set_boolean (value, gstbin->priv->asynchandling);
578 GST_OBJECT_UNLOCK (gstbin);
580 case PROP_MESSAGE_FORWARD:
581 GST_OBJECT_LOCK (gstbin);
582 g_value_set_boolean (value, gstbin->priv->message_forward);
583 GST_OBJECT_UNLOCK (gstbin);
586 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
592 /* return the cached index */
594 gst_bin_get_index_func (GstElement * element)
599 bin = GST_BIN_CAST (element);
601 GST_OBJECT_LOCK (bin);
602 if ((result = bin->priv->index))
603 gst_object_ref (result);
604 GST_OBJECT_UNLOCK (bin);
609 /* set the index on all elements in this bin
614 gst_bin_set_index_func (GstElement * element, GstIndex * index)
620 GValue data = { 0, };
622 bin = GST_BIN_CAST (element);
624 GST_OBJECT_LOCK (bin);
625 old = bin->priv->index;
626 if (G_UNLIKELY (old == index))
629 gst_object_ref (index);
630 bin->priv->index = index;
631 GST_OBJECT_UNLOCK (bin);
634 gst_object_unref (old);
636 it = gst_bin_iterate_elements (bin);
638 /* set the index on all elements in the bin */
641 switch (gst_iterator_next (it, &data)) {
642 case GST_ITERATOR_OK:
644 GstElement *child = g_value_get_object (&data);
646 GST_DEBUG_OBJECT (bin, "setting index on '%s'",
647 GST_ELEMENT_NAME (child));
648 gst_element_set_index (child, index);
650 g_value_reset (&data);
653 case GST_ITERATOR_RESYNC:
654 GST_DEBUG_OBJECT (bin, "iterator doing resync");
655 gst_iterator_resync (it);
658 case GST_ITERATOR_DONE:
659 GST_DEBUG_OBJECT (bin, "iterator done");
664 g_value_unset (&data);
665 gst_iterator_free (it);
670 GST_DEBUG_OBJECT (bin, "index was already set");
671 GST_OBJECT_UNLOCK (bin);
677 /* set the clock on all elements in this bin
682 gst_bin_set_clock_func (GstElement * element, GstClock * clock)
688 GValue data = { 0, };
690 bin = GST_BIN_CAST (element);
692 it = gst_bin_iterate_elements (bin);
696 switch (gst_iterator_next (it, &data)) {
697 case GST_ITERATOR_OK:
699 GstElement *child = g_value_get_object (&data);
701 res &= gst_element_set_clock (child, clock);
703 g_value_reset (&data);
706 case GST_ITERATOR_RESYNC:
707 GST_DEBUG_OBJECT (bin, "iterator doing resync");
708 gst_iterator_resync (it);
712 case GST_ITERATOR_DONE:
713 GST_DEBUG_OBJECT (bin, "iterator done");
718 g_value_unset (&data);
719 gst_iterator_free (it);
722 res = GST_ELEMENT_CLASS (parent_class)->set_clock (element, clock);
727 /* get the clock for this bin by asking all of the children in this bin
729 * The ref of the returned clock in increased so unref after usage.
731 * We loop the elements in state order and pick the last clock we can
732 * get. This makes sure we get a clock from the source.
737 gst_bin_provide_clock_func (GstElement * element)
739 GstClock *result = NULL;
740 GstElement *provider = NULL;
745 GstClock **provided_clock_p;
746 GstElement **clock_provider_p;
748 bin = GST_BIN_CAST (element);
750 GST_OBJECT_LOCK (bin);
751 if (!bin->clock_dirty)
754 GST_DEBUG_OBJECT (bin, "finding new clock");
756 it = gst_bin_sort_iterator_new (bin);
757 GST_OBJECT_UNLOCK (bin);
761 switch (gst_iterator_next (it, &val)) {
762 case GST_ITERATOR_OK:
764 GstElement *child = g_value_get_object (&val);
767 clock = gst_element_provide_clock (child);
769 GST_DEBUG_OBJECT (bin, "found candidate clock %p by element %s",
770 clock, GST_ELEMENT_NAME (child));
772 gst_object_unref (result);
773 gst_object_unref (provider);
776 provider = gst_object_ref (child);
779 g_value_reset (&val);
782 case GST_ITERATOR_RESYNC:
783 gst_iterator_resync (it);
786 case GST_ITERATOR_DONE:
791 g_value_unset (&val);
792 gst_iterator_free (it);
794 GST_OBJECT_LOCK (bin);
795 if (!bin->clock_dirty) {
797 gst_object_unref (provider);
799 gst_object_unref (result);
805 provided_clock_p = &bin->provided_clock;
806 clock_provider_p = &bin->clock_provider;
807 gst_object_replace ((GstObject **) provided_clock_p, (GstObject *) result);
808 gst_object_replace ((GstObject **) clock_provider_p, (GstObject *) provider);
809 bin->clock_dirty = FALSE;
810 GST_DEBUG_OBJECT (bin,
811 "provided new clock %" GST_PTR_FORMAT " by provider %" GST_PTR_FORMAT,
813 /* Provider is not being returned to caller, just the result */
815 gst_object_unref (provider);
816 GST_OBJECT_UNLOCK (bin);
822 if ((result = bin->provided_clock))
823 gst_object_ref (result);
824 GST_DEBUG_OBJECT (bin, "returning old clock %p", result);
825 GST_OBJECT_UNLOCK (bin);
832 * functions for manipulating cached messages
837 GstMessageType types;
840 /* check if a message is of given src and type */
842 message_check (GstMessage * message, MessageFind * target)
847 eq &= GST_MESSAGE_SRC (message) == target->src;
849 eq &= (GST_MESSAGE_TYPE (message) & target->types) != 0;
850 GST_LOG ("looking at message %p: %d", message, eq);
856 find_message (GstBin * bin, GstObject * src, GstMessageType types)
864 result = g_list_find_custom (bin->messages, &find,
865 (GCompareFunc) message_check);
868 GST_DEBUG_OBJECT (bin, "we found a message %p from %s matching types %08x",
869 result->data, GST_OBJECT_NAME (GST_MESSAGE_CAST (result->data)->src),
872 GST_DEBUG_OBJECT (bin, "no message found matching types %08x", types);
873 #ifndef GST_DISABLE_GST_DEBUG
877 for (i = 0; i < 32; i++)
878 if (types & (1U << i))
879 GST_DEBUG_OBJECT (bin, " %s", gst_message_type_get_name (1U << i));
887 /* with LOCK, returns TRUE if message had a valid SRC, takes ownership of
890 * A message that is cached and has the same SRC and type is replaced
891 * by the given message.
894 bin_replace_message (GstBin * bin, GstMessage * message, GstMessageType types)
900 if ((src = GST_MESSAGE_SRC (message))) {
901 /* first find the previous message posted by this element */
902 if ((previous = find_message (bin, src, types))) {
903 GstMessage *previous_msg;
905 /* if we found a previous message, replace it */
906 previous_msg = previous->data;
907 previous->data = message;
909 GST_DEBUG_OBJECT (bin, "replace old message %s from %s with %s message",
910 GST_MESSAGE_TYPE_NAME (previous_msg), GST_ELEMENT_NAME (src),
911 GST_MESSAGE_TYPE_NAME (message));
913 gst_message_unref (previous_msg);
915 /* keep new message */
916 bin->messages = g_list_prepend (bin->messages, message);
918 GST_DEBUG_OBJECT (bin, "got new message %p, %s from %s",
919 message, GST_MESSAGE_TYPE_NAME (message), GST_ELEMENT_NAME (src));
922 GST_DEBUG_OBJECT (bin, "got message %s from (NULL), not processing",
923 GST_MESSAGE_TYPE_NAME (message));
925 gst_message_unref (message);
930 /* with LOCK. Remove all messages of given types */
932 bin_remove_messages (GstBin * bin, GstObject * src, GstMessageType types)
940 for (walk = bin->messages; walk; walk = next) {
941 GstMessage *message = (GstMessage *) walk->data;
943 next = g_list_next (walk);
945 if (message_check (message, &find) == 0) {
946 GST_DEBUG_OBJECT (GST_MESSAGE_SRC (message),
947 "deleting message %p of types 0x%08x", message, types);
948 bin->messages = g_list_delete_link (bin->messages, walk);
949 gst_message_unref (message);
951 GST_DEBUG_OBJECT (GST_MESSAGE_SRC (message),
952 "not deleting message %p of type 0x%08x", message,
953 GST_MESSAGE_TYPE (message));
959 /* Check if the bin is EOS. We do this by scanning all sinks and
960 * checking if they posted an EOS message.
962 * call with bin LOCK */
964 is_eos (GstBin * bin, guint32 * seqnum)
971 for (walk = bin->children; walk; walk = g_list_next (walk)) {
974 element = GST_ELEMENT_CAST (walk->data);
975 if (bin_element_is_sink (element, bin) == 0) {
976 /* check if element posted EOS */
978 find_message (bin, GST_OBJECT_CAST (element), GST_MESSAGE_EOS))) {
979 GST_DEBUG ("sink '%s' posted EOS", GST_ELEMENT_NAME (element));
980 *seqnum = gst_message_get_seqnum (GST_MESSAGE_CAST (msgs->data));
983 GST_DEBUG ("sink '%s' did not post EOS yet",
984 GST_ELEMENT_NAME (element));
990 /* FIXME: Some tests (e.g. elements/capsfilter) use
991 * pipelines with a dangling sinkpad but no sink element.
992 * These tests assume that no EOS message is ever
993 * posted on the bus so let's keep that behaviour.
994 * In valid pipelines this doesn't make a difference.
996 return result && n_eos > 0;
1000 /* Check if the bin is STREAM_START. We do this by scanning all sinks and
1001 * checking if they posted an STREAM_START message.
1003 * call with bin LOCK */
1005 is_stream_start (GstBin * bin, guint32 * seqnum, gboolean * have_group_id,
1011 gboolean first = TRUE, same_group_id = TRUE;
1013 *have_group_id = TRUE;
1016 for (walk = bin->children; walk; walk = g_list_next (walk)) {
1017 GstElement *element;
1019 element = GST_ELEMENT_CAST (walk->data);
1020 if (bin_element_is_sink (element, bin) == 0) {
1021 /* check if element posted STREAM_START */
1023 find_message (bin, GST_OBJECT_CAST (element),
1024 GST_MESSAGE_STREAM_START))) {
1025 GST_DEBUG ("sink '%s' posted STREAM_START", GST_ELEMENT_NAME (element));
1026 *seqnum = gst_message_get_seqnum (GST_MESSAGE_CAST (msgs->data));
1027 if (gst_message_parse_group_id (GST_MESSAGE_CAST (msgs->data),
1031 *group_id = tmp_group_id;
1033 if (tmp_group_id != *group_id)
1034 same_group_id = FALSE;
1037 *have_group_id = FALSE;
1040 GST_DEBUG ("sink '%s' did not post STREAM_START yet",
1041 GST_ELEMENT_NAME (element));
1048 /* If all have a group_id we only consider this stream started
1049 * if all group ids were the same and all sinks posted a stream-start
1052 return same_group_id && result;
1053 /* otherwise consider this stream started after all sinks
1054 * have reported stream-start for backward compatibility.
1055 * FIXME 2.0: This should go away! */
1060 unlink_pads (const GValue * item, gpointer user_data)
1065 pad = g_value_get_object (item);
1067 if ((peer = gst_pad_get_peer (pad))) {
1068 if (gst_pad_get_direction (pad) == GST_PAD_SRC)
1069 gst_pad_unlink (pad, peer);
1071 gst_pad_unlink (peer, pad);
1072 gst_object_unref (peer);
1076 /* vmethod that adds an element to a bin
1081 gst_bin_add_func (GstBin * bin, GstElement * element)
1085 gboolean is_sink, is_source, provides_clock, requires_clock;
1086 GstMessage *clock_message = NULL, *async_message = NULL;
1087 GstStateChangeReturn ret;
1088 GList *l, *elem_contexts, *need_context_messages;
1090 GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
1092 /* we obviously can't add ourself to ourself */
1093 if (G_UNLIKELY (element == GST_ELEMENT_CAST (bin)))
1096 /* get the element name to make sure it is unique in this bin. */
1097 GST_OBJECT_LOCK (element);
1098 elem_name = g_strdup (GST_ELEMENT_NAME (element));
1099 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1100 is_source = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE);
1102 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1104 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1105 GST_OBJECT_UNLOCK (element);
1107 GST_OBJECT_LOCK (bin);
1109 /* then check to see if the element's name is already taken in the bin,
1110 * we can safely take the lock here. This check is probably bogus because
1111 * you can safely change the element name after this check and before setting
1112 * the object parent. The window is very small though... */
1113 if (G_UNLIKELY (!gst_object_check_uniqueness (bin->children, elem_name)))
1114 goto duplicate_name;
1116 /* set the element's parent and add the element to the bin's list of children */
1117 if (G_UNLIKELY (!gst_object_set_parent (GST_OBJECT_CAST (element),
1118 GST_OBJECT_CAST (bin))))
1121 /* if we add a sink we become a sink */
1123 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "element \"%s\" was sink",
1125 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_SINK);
1128 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "element \"%s\" was source",
1130 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_SOURCE);
1132 if (provides_clock) {
1133 GST_DEBUG_OBJECT (bin, "element \"%s\" can provide a clock", elem_name);
1135 gst_message_new_clock_provide (GST_OBJECT_CAST (element), NULL, TRUE);
1136 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1138 if (requires_clock) {
1139 GST_DEBUG_OBJECT (bin, "element \"%s\" requires a clock", elem_name);
1140 GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1143 bin->children = g_list_prepend (bin->children, element);
1145 bin->children_cookie++;
1146 if (!GST_BIN_IS_NO_RESYNC (bin))
1147 bin->priv->structure_cookie++;
1149 /* distribute the bus */
1150 gst_element_set_bus (element, bin->child_bus);
1152 /* propagate the current base_time, start_time and clock */
1153 gst_element_set_base_time (element, GST_ELEMENT_CAST (bin)->base_time);
1154 gst_element_set_start_time (element, GST_ELEMENT_START_TIME (bin));
1155 /* it's possible that the element did not accept the clock but
1156 * that is not important right now. When the pipeline goes to PLAYING,
1157 * a new clock will be selected */
1158 gst_element_set_clock (element, GST_ELEMENT_CLOCK (bin));
1160 /* get the element's list of contexts before propagating our own */
1161 elem_contexts = gst_element_get_contexts (element);
1162 for (l = GST_ELEMENT_CAST (bin)->contexts; l; l = l->next)
1163 gst_element_set_context (element, l->data);
1165 need_context_messages = NULL;
1166 for (l = elem_contexts; l; l = l->next) {
1167 GstContext *replacement, *context = l->data;
1168 const gchar *context_type;
1170 context_type = gst_context_get_context_type (context);
1172 /* we already set this context above? */
1174 gst_element_get_context_unlocked (GST_ELEMENT (bin), context_type);
1176 gst_context_unref (replacement);
1181 /* ask our parent for the context */
1182 msg = gst_message_new_need_context (GST_OBJECT_CAST (bin), context_type);
1183 s = (GstStructure *) gst_message_get_structure (msg);
1184 gst_structure_set (s, "bin.old.context", GST_TYPE_CONTEXT, context, NULL);
1186 need_context_messages = g_list_prepend (need_context_messages, msg);
1191 /* set the cached index on the children */
1192 if (bin->priv->index)
1193 gst_element_set_index (element, bin->priv->index);
1196 ret = GST_STATE_RETURN (bin);
1197 /* no need to update the state if we are in error */
1198 if (ret == GST_STATE_CHANGE_FAILURE)
1199 goto no_state_recalc;
1201 /* update the bin state, the new element could have been an ASYNC or
1202 * NO_PREROLL element */
1203 ret = GST_STATE_RETURN (element);
1204 GST_DEBUG_OBJECT (bin, "added %s element",
1205 gst_element_state_change_return_get_name (ret));
1208 case GST_STATE_CHANGE_ASYNC:
1210 /* create message to track this aync element when it posts an async-done
1212 async_message = gst_message_new_async_start (GST_OBJECT_CAST (element));
1215 case GST_STATE_CHANGE_NO_PREROLL:
1216 /* ignore all async elements we might have and commit our state */
1217 bin_handle_async_done (bin, ret, FALSE, GST_CLOCK_TIME_NONE);
1219 case GST_STATE_CHANGE_FAILURE:
1226 GST_OBJECT_UNLOCK (bin);
1228 for (l = need_context_messages; l; l = l->next) {
1229 GstMessage *msg = l->data;
1231 const gchar *context_type;
1232 GstContext *replacement, *context;
1234 gst_message_parse_context_type (msg, &context_type);
1236 GST_LOG_OBJECT (bin, "asking parent for context type: %s "
1237 "from %" GST_PTR_FORMAT, context_type, element);
1239 s = (GstStructure *) gst_message_get_structure (msg);
1240 gst_structure_get (s, "bin.old.context", GST_TYPE_CONTEXT, &context, NULL);
1241 gst_structure_remove_field (s, "bin.old.context");
1242 gst_element_post_message (GST_ELEMENT_CAST (bin), msg);
1244 /* lock to avoid losing a potential write */
1245 GST_OBJECT_LOCK (bin);
1247 gst_element_get_context_unlocked (GST_ELEMENT_CAST (bin), context_type);
1250 /* we got the context set from GstElement::set_context */
1251 gst_context_unref (replacement);
1252 GST_OBJECT_UNLOCK (bin);
1254 /* Propagate the element's context upwards */
1255 GST_LOG_OBJECT (bin, "propagating existing context type: %s %p "
1256 "from %" GST_PTR_FORMAT, context_type, context, element);
1258 gst_bin_update_context_unlocked (bin, context);
1261 gst_message_new_have_context (GST_OBJECT_CAST (bin),
1262 gst_context_ref (context));
1263 GST_OBJECT_UNLOCK (bin);
1264 gst_element_post_message (GST_ELEMENT_CAST (bin), msg);
1266 gst_context_unref (context);
1268 g_list_free_full (elem_contexts, (GDestroyNotify) gst_context_unref);
1269 g_list_free (need_context_messages);
1271 /* post the messages on the bus of the element so that the bin can handle
1274 gst_element_post_message (element, clock_message);
1277 gst_element_post_message (element, async_message);
1279 /* unlink all linked pads */
1280 it = gst_element_iterate_pads (element);
1281 gst_iterator_foreach (it, (GstIteratorForeachFunction) unlink_pads, NULL);
1282 gst_iterator_free (it);
1284 GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "added element \"%s\"",
1287 g_signal_emit (bin, gst_bin_signals[ELEMENT_ADDED], 0, element);
1288 gst_child_proxy_child_added ((GstChildProxy *) bin, (GObject *) element,
1295 /* ERROR handling here */
1298 GST_OBJECT_LOCK (bin);
1299 g_warning ("Cannot add bin '%s' to itself", GST_ELEMENT_NAME (bin));
1300 GST_OBJECT_UNLOCK (bin);
1305 g_warning ("Name '%s' is not unique in bin '%s', not adding",
1306 elem_name, GST_ELEMENT_NAME (bin));
1307 GST_OBJECT_UNLOCK (bin);
1313 g_warning ("Element '%s' already has parent", elem_name);
1314 GST_OBJECT_UNLOCK (bin);
1323 * @element: (transfer full): the #GstElement to add
1325 * Adds the given element to the bin. Sets the element's parent, and thus
1326 * takes ownership of the element. An element can only be added to one bin.
1328 * If the element's pads are linked to other pads, the pads will be unlinked
1329 * before the element is added to the bin.
1332 * When you add an element to an already-running pipeline, you will have to
1333 * take care to set the state of the newly-added element to the desired
1334 * state (usually PLAYING or PAUSED, same you set the pipeline to originally)
1335 * with gst_element_set_state(), or use gst_element_sync_state_with_parent().
1336 * The bin or pipeline will not take care of this for you.
1341 * Returns: %TRUE if the element could be added, %FALSE if
1342 * the bin does not want to accept the element.
1345 gst_bin_add (GstBin * bin, GstElement * element)
1347 GstBinClass *bclass;
1350 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
1351 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
1352 g_return_val_if_fail (GST_ELEMENT_CAST (bin) != element, FALSE);
1354 bclass = GST_BIN_GET_CLASS (bin);
1356 if (G_UNLIKELY (bclass->add_element == NULL))
1359 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "adding element %s to bin %s",
1360 GST_STR_NULL (GST_ELEMENT_NAME (element)),
1361 GST_STR_NULL (GST_ELEMENT_NAME (bin)));
1363 GST_TRACER_BIN_ADD_PRE (bin, element);
1364 result = bclass->add_element (bin, element);
1365 GST_TRACER_BIN_ADD_POST (bin, element, result);
1369 /* ERROR handling */
1372 g_warning ("adding elements to bin '%s' is not supported",
1373 GST_ELEMENT_NAME (bin));
1378 /* remove an element from the bin
1383 gst_bin_remove_func (GstBin * bin, GstElement * element)
1387 gboolean is_sink, is_source, provides_clock, requires_clock;
1388 gboolean othersink, othersource, otherprovider, otherrequirer, found;
1389 GstMessage *clock_message = NULL;
1390 GstClock **provided_clock_p;
1391 GstElement **clock_provider_p;
1393 gboolean other_async, this_async, have_no_preroll;
1394 GstStateChangeReturn ret;
1396 GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
1398 /* we obviously can't remove ourself from ourself */
1399 if (G_UNLIKELY (element == GST_ELEMENT_CAST (bin)))
1400 goto removing_itself;
1402 GST_OBJECT_LOCK (bin);
1404 GST_OBJECT_LOCK (element);
1405 elem_name = g_strdup (GST_ELEMENT_NAME (element));
1407 if (GST_OBJECT_PARENT (element) != GST_OBJECT_CAST (bin))
1410 /* remove the parent ref */
1411 GST_OBJECT_PARENT (element) = NULL;
1413 /* grab element name so we can print it */
1414 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
1415 is_source = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SOURCE);
1417 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1419 GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1420 GST_OBJECT_UNLOCK (element);
1424 othersource = FALSE;
1425 otherprovider = FALSE;
1426 otherrequirer = FALSE;
1427 have_no_preroll = FALSE;
1428 /* iterate the elements, we collect which ones are async and no_preroll. We
1429 * also remove the element when we find it. */
1430 for (walk = bin->children; walk; walk = next) {
1431 GstElement *child = GST_ELEMENT_CAST (walk->data);
1433 next = g_list_next (walk);
1435 if (child == element) {
1437 /* remove the element */
1438 bin->children = g_list_delete_link (bin->children, walk);
1440 gboolean child_sink, child_source, child_provider, child_requirer;
1442 GST_OBJECT_LOCK (child);
1443 child_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1444 child_source = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
1446 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1448 GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1449 /* when we remove a sink, check if there are other sinks. */
1450 if (is_sink && !othersink && child_sink)
1452 if (is_source && !othersource && child_source)
1454 if (provides_clock && !otherprovider && child_provider)
1455 otherprovider = TRUE;
1456 if (requires_clock && !otherrequirer && child_requirer)
1457 otherrequirer = TRUE;
1458 /* check if we have NO_PREROLL children */
1459 if (GST_STATE_RETURN (child) == GST_STATE_CHANGE_NO_PREROLL)
1460 have_no_preroll = TRUE;
1461 GST_OBJECT_UNLOCK (child);
1465 /* the element must have been in the bin's list of children */
1466 if (G_UNLIKELY (!found))
1469 /* we now removed the element from the list of elements, increment the cookie
1470 * so that others can detect a change in the children list. */
1472 bin->children_cookie++;
1473 if (!GST_BIN_IS_NO_RESYNC (bin))
1474 bin->priv->structure_cookie++;
1476 if (is_sink && !othersink) {
1477 /* we're not a sink anymore */
1478 GST_DEBUG_OBJECT (bin, "we removed the last sink");
1479 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SINK);
1481 if (is_source && !othersource) {
1482 /* we're not a source anymore */
1483 GST_DEBUG_OBJECT (bin, "we removed the last source");
1484 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_SOURCE);
1486 if (provides_clock && !otherprovider) {
1487 /* we're not a clock provider anymore */
1488 GST_DEBUG_OBJECT (bin, "we removed the last clock provider");
1489 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_PROVIDE_CLOCK);
1491 if (requires_clock && !otherrequirer) {
1492 /* we're not a clock requirer anymore */
1493 GST_DEBUG_OBJECT (bin, "we removed the last clock requirer");
1494 GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_FLAG_REQUIRE_CLOCK);
1497 /* if the clock provider for this element is removed, we lost
1498 * the clock as well, we need to inform the parent of this
1499 * so that it can select a new clock */
1500 if (bin->clock_provider == element) {
1501 GST_DEBUG_OBJECT (bin, "element \"%s\" provided the clock", elem_name);
1502 bin->clock_dirty = TRUE;
1504 gst_message_new_clock_lost (GST_OBJECT_CAST (bin), bin->provided_clock);
1505 provided_clock_p = &bin->provided_clock;
1506 clock_provider_p = &bin->clock_provider;
1507 gst_object_replace ((GstObject **) provided_clock_p, NULL);
1508 gst_object_replace ((GstObject **) clock_provider_p, NULL);
1511 /* remove messages for the element, if there was a pending ASYNC_START
1512 * message we must see if removing the element caused the bin to lose its
1515 other_async = FALSE;
1516 for (walk = bin->messages; walk; walk = next) {
1517 GstMessage *message = (GstMessage *) walk->data;
1518 GstElement *src = GST_ELEMENT_CAST (GST_MESSAGE_SRC (message));
1521 next = g_list_next (walk);
1524 switch (GST_MESSAGE_TYPE (message)) {
1525 case GST_MESSAGE_ASYNC_START:
1531 GST_DEBUG_OBJECT (src, "looking at message %p", message);
1533 case GST_MESSAGE_STRUCTURE_CHANGE:
1537 GST_DEBUG_OBJECT (src, "looking at structure change message %p",
1539 /* it's unlikely that this message is still in the list of messages
1540 * because this would mean that a link/unlink is busy in another thread
1541 * while we remove the element. We still have to remove the message
1542 * because we might not receive the done message anymore when the element
1543 * is removed from the bin. */
1544 gst_message_parse_structure_change (message, NULL, &owner, NULL);
1545 if (owner == element)
1556 /* delete all message types */
1557 GST_DEBUG_OBJECT (src, "deleting message %p of element \"%s\"",
1558 message, elem_name);
1559 bin->messages = g_list_delete_link (bin->messages, walk);
1560 gst_message_unref (message);
1564 /* get last return */
1565 ret = GST_STATE_RETURN (bin);
1567 /* no need to update the state if we are in error */
1568 if (ret == GST_STATE_CHANGE_FAILURE)
1569 goto no_state_recalc;
1571 if (!other_async && this_async) {
1572 /* all other elements were not async and we removed the async one,
1573 * handle the async-done case because we are not async anymore now. */
1574 GST_DEBUG_OBJECT (bin,
1575 "we removed the last async element, have no_preroll %d",
1578 /* the current state return of the bin depends on if there are no_preroll
1579 * elements in the pipeline or not */
1580 if (have_no_preroll)
1581 ret = GST_STATE_CHANGE_NO_PREROLL;
1583 ret = GST_STATE_CHANGE_SUCCESS;
1585 bin_handle_async_done (bin, ret, FALSE, GST_CLOCK_TIME_NONE);
1587 GST_DEBUG_OBJECT (bin,
1588 "recalc state preroll: %d, other async: %d, this async %d",
1589 have_no_preroll, other_async, this_async);
1591 if (have_no_preroll) {
1592 ret = GST_STATE_CHANGE_NO_PREROLL;
1593 } else if (other_async) {
1594 /* there are other async elements and we were not doing an async state
1595 * change, change our pending state and go async */
1596 if (GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING) {
1597 GST_STATE_NEXT (bin) = GST_STATE (bin);
1598 GST_STATE_PENDING (bin) = GST_STATE (bin);
1600 ret = GST_STATE_CHANGE_ASYNC;
1602 GST_STATE_RETURN (bin) = ret;
1606 gst_element_set_bus (element, NULL);
1607 /* Clear the clock we provided to the element */
1608 gst_element_set_clock (element, NULL);
1609 GST_OBJECT_UNLOCK (bin);
1612 gst_element_post_message (GST_ELEMENT_CAST (bin), clock_message);
1614 /* unlink all linked pads */
1615 it = gst_element_iterate_pads (element);
1616 gst_iterator_foreach (it, (GstIteratorForeachFunction) unlink_pads, NULL);
1617 gst_iterator_free (it);
1619 GST_CAT_INFO_OBJECT (GST_CAT_PARENTAGE, bin, "removed child \"%s\"",
1622 g_signal_emit (bin, gst_bin_signals[ELEMENT_REMOVED], 0, element);
1623 gst_child_proxy_child_removed ((GstChildProxy *) bin, (GObject *) element,
1627 /* element is really out of our control now */
1628 gst_object_unref (element);
1632 /* ERROR handling */
1635 GST_OBJECT_LOCK (bin);
1636 g_warning ("Cannot remove bin '%s' from itself", GST_ELEMENT_NAME (bin));
1637 GST_OBJECT_UNLOCK (bin);
1642 g_warning ("Element '%s' is not in bin '%s'", elem_name,
1643 GST_ELEMENT_NAME (bin));
1644 GST_OBJECT_UNLOCK (element);
1645 GST_OBJECT_UNLOCK (bin);
1654 * @element: (transfer none): the #GstElement to remove
1656 * Removes the element from the bin, unparenting it as well.
1657 * Unparenting the element means that the element will be dereferenced,
1658 * so if the bin holds the only reference to the element, the element
1659 * will be freed in the process of removing it from the bin. If you
1660 * want the element to still exist after removing, you need to call
1661 * gst_object_ref() before removing it from the bin.
1663 * If the element's pads are linked to other pads, the pads will be unlinked
1664 * before the element is removed from the bin.
1668 * Returns: %TRUE if the element could be removed, %FALSE if
1669 * the bin does not want to remove the element.
1672 gst_bin_remove (GstBin * bin, GstElement * element)
1674 GstBinClass *bclass;
1677 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
1678 g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
1679 g_return_val_if_fail (GST_ELEMENT_CAST (bin) != element, FALSE);
1681 bclass = GST_BIN_GET_CLASS (bin);
1683 if (G_UNLIKELY (bclass->remove_element == NULL))
1686 GST_CAT_DEBUG (GST_CAT_PARENTAGE, "removing element %s from bin %s",
1687 GST_ELEMENT_NAME (element), GST_ELEMENT_NAME (bin));
1689 GST_TRACER_BIN_REMOVE_PRE (bin, element);
1690 result = bclass->remove_element (bin, element);
1691 GST_TRACER_BIN_REMOVE_POST (bin, result);
1695 /* ERROR handling */
1698 g_warning ("removing elements from bin '%s' is not supported",
1699 GST_ELEMENT_NAME (bin));
1705 * gst_bin_iterate_elements:
1708 * Gets an iterator for the elements in this bin.
1710 * MT safe. Caller owns returned value.
1712 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
1716 gst_bin_iterate_elements (GstBin * bin)
1718 GstIterator *result;
1720 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1722 GST_OBJECT_LOCK (bin);
1723 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1724 GST_OBJECT_GET_LOCK (bin),
1725 &bin->children_cookie, &bin->children, (GObject *) bin, NULL);
1726 GST_OBJECT_UNLOCK (bin);
1731 static GstIteratorItem
1732 iterate_child_recurse (GstIterator * it, const GValue * item)
1734 GstElement *child = g_value_get_object (item);
1736 if (GST_IS_BIN (child)) {
1737 GstIterator *other = gst_bin_iterate_recurse (GST_BIN_CAST (child));
1739 gst_iterator_push (it, other);
1741 return GST_ITERATOR_ITEM_PASS;
1745 * gst_bin_iterate_recurse:
1748 * Gets an iterator for the elements in this bin.
1749 * This iterator recurses into GstBin children.
1751 * MT safe. Caller owns returned value.
1753 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
1757 gst_bin_iterate_recurse (GstBin * bin)
1759 GstIterator *result;
1761 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1763 GST_OBJECT_LOCK (bin);
1764 result = gst_iterator_new_list (GST_TYPE_ELEMENT,
1765 GST_OBJECT_GET_LOCK (bin),
1766 &bin->children_cookie,
1768 (GObject *) bin, (GstIteratorItemFunction) iterate_child_recurse);
1769 GST_OBJECT_UNLOCK (bin);
1774 /* returns 0 when TRUE because this is a GCompareFunc */
1777 bin_element_is_sink (GstElement * child, GstBin * bin)
1781 /* we lock the child here for the remainder of the function to
1782 * get its name and flag safely. */
1783 GST_OBJECT_LOCK (child);
1784 is_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SINK);
1786 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
1787 "child %s %s sink", GST_OBJECT_NAME (child), is_sink ? "is" : "is not");
1789 GST_OBJECT_UNLOCK (child);
1790 return is_sink ? 0 : 1;
1794 sink_iterator_filter (const GValue * vchild, GValue * vbin)
1796 GstBin *bin = g_value_get_object (vbin);
1797 GstElement *child = g_value_get_object (vchild);
1799 return (bin_element_is_sink (child, bin));
1803 * gst_bin_iterate_sinks:
1806 * Gets an iterator for all elements in the bin that have the
1807 * #GST_ELEMENT_FLAG_SINK flag set.
1809 * MT safe. Caller owns returned value.
1811 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
1815 gst_bin_iterate_sinks (GstBin * bin)
1817 GstIterator *children;
1818 GstIterator *result;
1819 GValue vbin = { 0, };
1821 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1823 g_value_init (&vbin, GST_TYPE_BIN);
1824 g_value_set_object (&vbin, bin);
1826 children = gst_bin_iterate_elements (bin);
1827 result = gst_iterator_filter (children,
1828 (GCompareFunc) sink_iterator_filter, &vbin);
1830 g_value_unset (&vbin);
1835 /* returns 0 when TRUE because this is a GCompareFunc */
1838 bin_element_is_src (GstElement * child, GstBin * bin)
1842 /* we lock the child here for the remainder of the function to
1843 * get its name and other info safely. */
1844 GST_OBJECT_LOCK (child);
1845 is_src = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_FLAG_SOURCE);
1847 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
1848 "child %s %s src", GST_OBJECT_NAME (child), is_src ? "is" : "is not");
1850 GST_OBJECT_UNLOCK (child);
1851 return is_src ? 0 : 1;
1855 src_iterator_filter (const GValue * vchild, GValue * vbin)
1857 GstBin *bin = g_value_get_object (vbin);
1858 GstElement *child = g_value_get_object (vchild);
1860 return (bin_element_is_src (child, bin));
1864 * gst_bin_iterate_sources:
1867 * Gets an iterator for all elements in the bin that have the
1868 * #GST_ELEMENT_FLAG_SOURCE flag set.
1870 * MT safe. Caller owns returned value.
1872 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
1876 gst_bin_iterate_sources (GstBin * bin)
1878 GstIterator *children;
1879 GstIterator *result;
1880 GValue vbin = { 0, };
1882 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
1884 g_value_init (&vbin, GST_TYPE_BIN);
1885 g_value_set_object (&vbin, bin);
1887 children = gst_bin_iterate_elements (bin);
1888 result = gst_iterator_filter (children,
1889 (GCompareFunc) src_iterator_filter, &vbin);
1891 g_value_unset (&vbin);
1899 static GstStateChangeReturn
1900 gst_bin_get_state_func (GstElement * element, GstState * state,
1901 GstState * pending, GstClockTime timeout)
1903 GstStateChangeReturn ret;
1905 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "getting state");
1908 GST_ELEMENT_CLASS (parent_class)->get_state (element, state, pending,
1914 /***********************************************
1915 * Topologically sorted iterator
1916 * see http://en.wikipedia.org/wiki/Topological_sorting
1918 * For each element in the graph, an entry is kept in a HashTable
1919 * with its number of srcpad connections (degree).
1920 * We then change state of all elements without dependencies
1921 * (degree 0) and decrement the degree of all elements connected
1922 * on the sinkpads. When an element reaches degree 0, its state is
1924 * When all elements are handled the algorithm stops.
1926 typedef struct _GstBinSortIterator
1929 GQueue queue; /* elements queued for state change */
1930 GstBin *bin; /* bin we iterate */
1931 gint mode; /* adding or removing dependency */
1932 GstElement *best; /* next element with least dependencies */
1933 gint best_deg; /* best degree */
1934 GHashTable *hash; /* hashtable with element dependencies */
1935 gboolean dirty; /* we detected structure change */
1936 } GstBinSortIterator;
1939 gst_bin_sort_iterator_copy (const GstBinSortIterator * it,
1940 GstBinSortIterator * copy)
1942 GHashTableIter iter;
1943 gpointer key, value;
1945 copy->queue = it->queue;
1946 g_queue_foreach (©->queue, (GFunc) gst_object_ref, NULL);
1948 copy->bin = gst_object_ref (it->bin);
1950 copy->best = gst_object_ref (it->best);
1952 copy->hash = g_hash_table_new (NULL, NULL);
1953 g_hash_table_iter_init (&iter, it->hash);
1954 while (g_hash_table_iter_next (&iter, &key, &value))
1955 g_hash_table_insert (copy->hash, key, value);
1958 /* we add and subtract 1 to make sure we don't confuse NULL and 0 */
1959 #define HASH_SET_DEGREE(bit, elem, deg) \
1960 g_hash_table_replace (bit->hash, elem, GINT_TO_POINTER(deg+1))
1961 #define HASH_GET_DEGREE(bit, elem) \
1962 (GPOINTER_TO_INT(g_hash_table_lookup (bit->hash, elem))-1)
1964 /* add element to queue of next elements in the iterator.
1965 * We push at the tail to give higher priority elements a
1968 add_to_queue (GstBinSortIterator * bit, GstElement * element)
1970 GST_DEBUG_OBJECT (bit->bin, "adding '%s' to queue",
1971 GST_ELEMENT_NAME (element));
1972 gst_object_ref (element);
1973 g_queue_push_tail (&bit->queue, element);
1974 HASH_SET_DEGREE (bit, element, -1);
1978 remove_from_queue (GstBinSortIterator * bit, GstElement * element)
1982 if ((find = g_queue_find (&bit->queue, element))) {
1983 GST_DEBUG_OBJECT (bit->bin, "removing '%s' from queue",
1984 GST_ELEMENT_NAME (element));
1986 g_queue_delete_link (&bit->queue, find);
1987 gst_object_unref (element);
1989 GST_DEBUG_OBJECT (bit->bin, "unable to remove '%s' from queue",
1990 GST_ELEMENT_NAME (element));
1994 /* clear the queue, unref all objects as we took a ref when
1995 * we added them to the queue */
1997 clear_queue (GQueue * queue)
2001 while ((p = g_queue_pop_head (queue)))
2002 gst_object_unref (p);
2005 /* set all degrees to 0. Elements marked as a sink are
2006 * added to the queue immediately. Since we only look at the SINK flag of the
2007 * element, it is possible that we add non-sinks to the queue. These will be
2008 * removed from the queue again when we can prove that it provides data for some
2011 reset_degree (GstElement * element, GstBinSortIterator * bit)
2015 /* sinks are added right away */
2016 GST_OBJECT_LOCK (element);
2017 is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_FLAG_SINK);
2018 GST_OBJECT_UNLOCK (element);
2021 add_to_queue (bit, element);
2023 /* others are marked with 0 and handled when sinks are done */
2024 HASH_SET_DEGREE (bit, element, 0);
2028 /* adjust the degree of all elements connected to the given
2029 * element. If a degree of an element drops to 0, it is
2030 * added to the queue of elements to schedule next.
2032 * We have to make sure not to cross the bin boundary this element
2036 update_degree (GstElement * element, GstBinSortIterator * bit)
2038 gboolean linked = FALSE;
2040 GST_OBJECT_LOCK (element);
2041 /* don't touch degree if element has no sinkpads */
2042 if (element->numsinkpads != 0) {
2043 /* loop over all sinkpads, decrement degree for all connected
2044 * elements in this bin */
2047 for (pads = element->sinkpads; pads; pads = g_list_next (pads)) {
2050 pad = GST_PAD_CAST (pads->data);
2052 /* we're iterating over the sinkpads, check if it's busy in a link/unlink */
2053 if (G_UNLIKELY (find_message (bit->bin, GST_OBJECT_CAST (pad),
2054 GST_MESSAGE_STRUCTURE_CHANGE))) {
2055 /* mark the iterator as dirty because we won't be updating the degree
2056 * of the peer parent now. This would result in the 'loop detected'
2057 * later on because the peer parent element could become the best next
2058 * element with a degree > 0. We will simply continue our state
2059 * changes and we'll eventually resync when the unlink completed and
2060 * the iterator cookie is updated. */
2065 if ((peer = gst_pad_get_peer (pad))) {
2066 GstElement *peer_element;
2068 if ((peer_element = gst_pad_get_parent_element (peer))) {
2069 GST_OBJECT_LOCK (peer_element);
2070 /* check that we don't go outside of this bin */
2071 if (GST_OBJECT_CAST (peer_element)->parent ==
2072 GST_OBJECT_CAST (bit->bin)) {
2073 gint old_deg, new_deg;
2075 old_deg = HASH_GET_DEGREE (bit, peer_element);
2077 /* check to see if we added an element as sink that was not really a
2078 * sink because it was connected to some other element. */
2079 if (old_deg == -1) {
2080 remove_from_queue (bit, peer_element);
2083 new_deg = old_deg + bit->mode;
2085 GST_DEBUG_OBJECT (bit->bin,
2086 "change element %s, degree %d->%d, linked to %s",
2087 GST_ELEMENT_NAME (peer_element), old_deg, new_deg,
2088 GST_ELEMENT_NAME (element));
2090 /* update degree, it is possible that an element was in 0 and
2091 * reaches -1 here. This would mean that the element had no sinkpads
2092 * but became linked while the state change was happening. We will
2093 * resync on this with the structure change message. */
2095 /* degree hit 0, add to queue */
2096 add_to_queue (bit, peer_element);
2098 HASH_SET_DEGREE (bit, peer_element, new_deg);
2102 GST_OBJECT_UNLOCK (peer_element);
2103 gst_object_unref (peer_element);
2105 gst_object_unref (peer);
2110 GST_DEBUG_OBJECT (bit->bin, "element %s not linked on any sinkpads",
2111 GST_ELEMENT_NAME (element));
2113 GST_OBJECT_UNLOCK (element);
2116 /* find the next best element not handled yet. This is the one
2117 * with the lowest non-negative degree */
2119 find_element (GstElement * element, GstBinSortIterator * bit)
2123 /* element is already handled */
2124 if ((degree = HASH_GET_DEGREE (bit, element)) < 0)
2127 /* first element or element with smaller degree */
2128 if (bit->best == NULL || bit->best_deg > degree) {
2129 bit->best = element;
2130 bit->best_deg = degree;
2134 /* get next element in iterator. */
2135 static GstIteratorResult
2136 gst_bin_sort_iterator_next (GstBinSortIterator * bit, GValue * result)
2139 GstBin *bin = bit->bin;
2141 /* empty queue, we have to find a next best element */
2142 if (g_queue_is_empty (&bit->queue)) {
2144 bit->best_deg = G_MAXINT;
2145 g_list_foreach (bin->children, (GFunc) find_element, bit);
2146 if ((best = bit->best)) {
2147 /* when we detected an unlink, don't warn because our degrees might be
2148 * screwed up. We will resync later */
2149 if (bit->best_deg != 0 && !bit->dirty) {
2150 /* we don't fail on this one yet */
2151 GST_WARNING_OBJECT (bin, "loop dected in graph");
2152 g_warning ("loop detected in the graph of bin '%s'!!",
2153 GST_ELEMENT_NAME (bin));
2155 /* best unhandled element, schedule as next element */
2156 GST_DEBUG_OBJECT (bin, "queue empty, next best: %s",
2157 GST_ELEMENT_NAME (best));
2158 HASH_SET_DEGREE (bit, best, -1);
2159 g_value_set_object (result, best);
2161 GST_DEBUG_OBJECT (bin, "queue empty, elements exhausted");
2162 /* no more unhandled elements, we are done */
2163 return GST_ITERATOR_DONE;
2166 /* everything added to the queue got reffed */
2167 best = g_queue_pop_head (&bit->queue);
2168 g_value_set_object (result, best);
2169 gst_object_unref (best);
2172 GST_DEBUG_OBJECT (bin, "queue head gives %s", GST_ELEMENT_NAME (best));
2173 /* update degrees of linked elements */
2174 update_degree (best, bit);
2176 return GST_ITERATOR_OK;
2179 /* clear queues, recalculate the degrees and restart. */
2181 gst_bin_sort_iterator_resync (GstBinSortIterator * bit)
2183 GstBin *bin = bit->bin;
2185 GST_DEBUG_OBJECT (bin, "resync");
2187 clear_queue (&bit->queue);
2189 g_list_foreach (bin->children, (GFunc) reset_degree, bit);
2190 /* calc degrees, incrementing */
2192 g_list_foreach (bin->children, (GFunc) update_degree, bit);
2193 /* for the rest of the function we decrement the degrees */
2197 /* clear queues, unref bin and free iterator. */
2199 gst_bin_sort_iterator_free (GstBinSortIterator * bit)
2201 GstBin *bin = bit->bin;
2203 GST_DEBUG_OBJECT (bin, "free");
2204 clear_queue (&bit->queue);
2205 g_hash_table_destroy (bit->hash);
2206 gst_object_unref (bin);
2209 /* should be called with the bin LOCK held */
2210 static GstIterator *
2211 gst_bin_sort_iterator_new (GstBin * bin)
2213 GstBinSortIterator *result;
2215 /* we don't need an ItemFunction because we ref the items in the _next
2217 result = (GstBinSortIterator *)
2218 gst_iterator_new (sizeof (GstBinSortIterator),
2220 GST_OBJECT_GET_LOCK (bin),
2221 &bin->priv->structure_cookie,
2222 (GstIteratorCopyFunction) gst_bin_sort_iterator_copy,
2223 (GstIteratorNextFunction) gst_bin_sort_iterator_next,
2224 (GstIteratorItemFunction) NULL,
2225 (GstIteratorResyncFunction) gst_bin_sort_iterator_resync,
2226 (GstIteratorFreeFunction) gst_bin_sort_iterator_free);
2227 g_queue_init (&result->queue);
2228 result->hash = g_hash_table_new (NULL, NULL);
2229 gst_object_ref (bin);
2231 gst_bin_sort_iterator_resync (result);
2233 return (GstIterator *) result;
2237 * gst_bin_iterate_sorted:
2240 * Gets an iterator for the elements in this bin in topologically
2241 * sorted order. This means that the elements are returned from
2242 * the most downstream elements (sinks) to the sources.
2244 * This function is used internally to perform the state changes
2245 * of the bin elements and for clock selection.
2247 * MT safe. Caller owns returned value.
2249 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement,
2253 gst_bin_iterate_sorted (GstBin * bin)
2255 GstIterator *result;
2257 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
2259 GST_OBJECT_LOCK (bin);
2260 result = gst_bin_sort_iterator_new (bin);
2261 GST_OBJECT_UNLOCK (bin);
2266 static GstStateChangeReturn
2267 gst_bin_element_set_state (GstBin * bin, GstElement * element,
2268 GstClockTime base_time, GstClockTime start_time, GstState current,
2271 GstStateChangeReturn ret;
2272 GstState child_current, child_pending;
2276 GST_STATE_LOCK (element);
2278 GST_OBJECT_LOCK (element);
2279 /* set base_time and start time on child */
2280 GST_ELEMENT_START_TIME (element) = start_time;
2281 element->base_time = base_time;
2282 /* peel off the locked flag */
2283 locked = GST_ELEMENT_IS_LOCKED_STATE (element);
2284 /* Get the previous set_state result to preserve NO_PREROLL and ASYNC */
2285 ret = GST_STATE_RETURN (element);
2286 child_current = GST_STATE (element);
2287 child_pending = GST_STATE_PENDING (element);
2288 GST_OBJECT_UNLOCK (element);
2290 /* skip locked elements */
2291 if (G_UNLIKELY (locked))
2294 /* if the element was no preroll, just start changing the state regardless
2295 * if it had async elements (in the case of a bin) because they won't preroll
2297 if (G_UNLIKELY (ret == GST_STATE_CHANGE_NO_PREROLL)) {
2298 GST_DEBUG_OBJECT (element, "element is NO_PREROLL, ignore async elements");
2302 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2303 "current %s pending %s, desired next %s",
2304 gst_element_state_get_name (child_current),
2305 gst_element_state_get_name (child_pending),
2306 gst_element_state_get_name (next));
2308 /* always recurse into bins so that we can set the base time */
2309 if (GST_IS_BIN (element))
2312 /* Try not to change the state of elements that are already in the state we're
2314 if (child_current == next && child_pending == GST_STATE_VOID_PENDING) {
2315 /* child is already at the requested state, return previous return. Note that
2316 * if the child has a pending state to next, we will still call the
2317 * set_state function */
2319 } else if (next > current) {
2320 /* upward state change */
2321 if (child_pending == GST_STATE_VOID_PENDING) {
2322 /* .. and the child is not busy doing anything */
2323 if (child_current > next) {
2324 /* .. and is already past the requested state, assume it got there
2326 ret = GST_STATE_CHANGE_SUCCESS;
2329 } else if (child_pending > child_current) {
2330 /* .. and the child is busy going upwards */
2331 if (child_current >= next) {
2332 /* .. and is already past the requested state, assume it got there
2334 ret = GST_STATE_CHANGE_SUCCESS;
2338 /* .. and the child is busy going downwards */
2339 if (child_current > next) {
2340 /* .. and is already past the requested state, assume it got there
2342 ret = GST_STATE_CHANGE_SUCCESS;
2346 } else if (next < current) {
2347 /* downward state change */
2348 if (child_pending == GST_STATE_VOID_PENDING) {
2349 /* .. and the child is not busy doing anything */
2350 if (child_current < next) {
2351 /* .. and is already past the requested state, assume it got there
2353 ret = GST_STATE_CHANGE_SUCCESS;
2356 } else if (child_pending < child_current) {
2357 /* .. and the child is busy going downwards */
2358 if (child_current <= next) {
2359 /* .. and is already past the requested state, assume it got there
2361 ret = GST_STATE_CHANGE_SUCCESS;
2365 /* .. and the child is busy going upwards */
2366 if (child_current < next) {
2367 /* .. and is already past the requested state, assume it got there
2369 ret = GST_STATE_CHANGE_SUCCESS;
2376 GST_OBJECT_LOCK (bin);
2377 /* the element was busy with an upwards async state change, we must wait for
2378 * an ASYNC_DONE message before we attemp to change the state. */
2380 find_message (bin, GST_OBJECT_CAST (element),
2381 GST_MESSAGE_ASYNC_START))) {
2382 #ifndef GST_DISABLE_GST_DEBUG
2383 GstMessage *message = GST_MESSAGE_CAST (found->data);
2385 GST_DEBUG_OBJECT (element, "element message %p, %s async busy",
2386 message, GST_ELEMENT_NAME (GST_MESSAGE_SRC (message)));
2388 /* only wait for upward state changes */
2389 if (next > current) {
2390 /* We found an async element check if we can force its state to change or
2391 * if we have to wait for it to preroll. */
2395 GST_OBJECT_UNLOCK (bin);
2398 GST_DEBUG_OBJECT (bin,
2399 "setting element %s to %s, base_time %" GST_TIME_FORMAT,
2400 GST_ELEMENT_NAME (element), gst_element_state_get_name (next),
2401 GST_TIME_ARGS (base_time));
2404 ret = gst_element_set_state (element, next);
2406 GST_STATE_UNLOCK (element);
2412 GST_DEBUG_OBJECT (element,
2413 "element is locked, return previous return %s",
2414 gst_element_state_change_return_get_name (ret));
2415 GST_STATE_UNLOCK (element);
2420 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2421 "skipping transition from %s to %s",
2422 gst_element_state_get_name (child_current),
2423 gst_element_state_get_name (next));
2424 GST_STATE_UNLOCK (element);
2429 GST_DEBUG_OBJECT (element, "element was busy, delaying state change");
2430 GST_OBJECT_UNLOCK (bin);
2431 GST_STATE_UNLOCK (element);
2432 return GST_STATE_CHANGE_ASYNC;
2436 /* gst_iterator_fold functions for pads_activate
2437 * Stop the iterator if activating one pad failed, but only if that pad
2438 * has not been removed from the element. */
2440 activate_pads (const GValue * vpad, GValue * ret, gboolean * active)
2442 GstPad *pad = g_value_get_object (vpad);
2443 gboolean cont = TRUE;
2445 if (!gst_pad_set_active (pad, *active)) {
2446 if (GST_PAD_PARENT (pad) != NULL) {
2448 g_value_set_boolean (ret, FALSE);
2455 /* returns false on error or early cutout of the fold, true if all
2456 * pads in @iter were (de)activated successfully. */
2458 iterator_activate_fold_with_resync (GstIterator * iter, gpointer user_data)
2460 GstIteratorResult ires;
2463 /* no need to unset this later, it's just a boolean */
2464 g_value_init (&ret, G_TYPE_BOOLEAN);
2465 g_value_set_boolean (&ret, TRUE);
2468 ires = gst_iterator_fold (iter, (GstIteratorFoldFunction) activate_pads,
2471 case GST_ITERATOR_RESYNC:
2472 /* need to reset the result again */
2473 g_value_set_boolean (&ret, TRUE);
2474 gst_iterator_resync (iter);
2476 case GST_ITERATOR_DONE:
2477 /* all pads iterated, return collected value */
2480 /* iterator returned _ERROR or premature end with _OK,
2481 * mark an error and exit */
2482 g_value_set_boolean (&ret, FALSE);
2487 /* return collected value */
2488 return g_value_get_boolean (&ret);
2491 /* is called with STATE_LOCK
2494 gst_bin_src_pads_activate (GstBin * bin, gboolean active)
2499 GST_DEBUG_OBJECT (bin, "%s pads", active ? "activate" : "deactivate");
2501 iter = gst_element_iterate_src_pads ((GstElement *) bin);
2502 fold_ok = iterator_activate_fold_with_resync (iter, &active);
2503 gst_iterator_free (iter);
2504 if (G_UNLIKELY (!fold_ok))
2507 GST_DEBUG_OBJECT (bin, "pad %sactivation successful", active ? "" : "de");
2514 GST_DEBUG_OBJECT (bin, "pad %sactivation failed", active ? "" : "de");
2520 * gst_bin_recalculate_latency:
2523 * Query @bin for the current latency using and reconfigures this latency to all the
2524 * elements with a LATENCY event.
2526 * This method is typically called on the pipeline when a #GST_MESSAGE_LATENCY
2527 * is posted on the bus.
2529 * This function simply emits the 'do-latency' signal so any custom latency
2530 * calculations will be performed.
2532 * Returns: %TRUE if the latency could be queried and reconfigured.
2535 gst_bin_recalculate_latency (GstBin * bin)
2539 g_signal_emit (bin, gst_bin_signals[DO_LATENCY], 0, &res);
2540 GST_DEBUG_OBJECT (bin, "latency returned %d", res);
2546 gst_bin_do_latency_func (GstBin * bin)
2549 GstElement *element;
2550 GstClockTime min_latency, max_latency;
2553 g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
2555 element = GST_ELEMENT_CAST (bin);
2557 GST_DEBUG_OBJECT (element, "querying latency");
2559 query = gst_query_new_latency ();
2560 if ((res = gst_element_query (element, query))) {
2563 gst_query_parse_latency (query, &live, &min_latency, &max_latency);
2565 GST_DEBUG_OBJECT (element,
2566 "got min latency %" GST_TIME_FORMAT ", max latency %"
2567 GST_TIME_FORMAT ", live %d", GST_TIME_ARGS (min_latency),
2568 GST_TIME_ARGS (max_latency), live);
2570 if (max_latency < min_latency) {
2571 /* this is an impossible situation, some parts of the pipeline might not
2572 * work correctly. We post a warning for now. */
2573 GST_ELEMENT_WARNING (element, CORE, CLOCK, (NULL),
2574 ("Impossible to configure latency: max %" GST_TIME_FORMAT " < min %"
2575 GST_TIME_FORMAT ". Add queues or other buffering elements.",
2576 GST_TIME_ARGS (max_latency), GST_TIME_ARGS (min_latency)));
2579 /* configure latency on elements */
2580 res = gst_element_send_event (element, gst_event_new_latency (min_latency));
2582 GST_INFO_OBJECT (element, "configured latency of %" GST_TIME_FORMAT,
2583 GST_TIME_ARGS (min_latency));
2585 GST_WARNING_OBJECT (element,
2586 "did not really configure latency of %" GST_TIME_FORMAT,
2587 GST_TIME_ARGS (min_latency));
2590 /* this is not a real problem, we just don't configure any latency. */
2591 GST_WARNING_OBJECT (element, "failed to query latency");
2593 gst_query_unref (query);
2599 gst_bin_post_message (GstElement * element, GstMessage * msg)
2601 GstElementClass *pklass = (GstElementClass *) parent_class;
2604 ret = pklass->post_message (element, gst_message_ref (msg));
2606 if (GST_MESSAGE_TYPE (msg) == GST_MESSAGE_STATE_CHANGED &&
2607 GST_MESSAGE_SRC (msg) == GST_OBJECT_CAST (element)) {
2608 GstState newstate, pending;
2610 gst_message_parse_state_changed (msg, NULL, &newstate, &pending);
2611 if (newstate == GST_STATE_PLAYING && pending == GST_STATE_VOID_PENDING) {
2612 GST_BIN_CAST (element)->priv->posted_playing = TRUE;
2613 bin_do_eos (GST_BIN_CAST (element));
2615 GST_BIN_CAST (element)->priv->posted_playing = FALSE;
2619 gst_message_unref (msg);
2625 reset_state (const GValue * data, gpointer user_data)
2627 GstElement *e = g_value_get_object (data);
2628 GstState state = GPOINTER_TO_INT (user_data);
2630 if (gst_element_set_state (e, state) == GST_STATE_CHANGE_FAILURE)
2631 GST_WARNING_OBJECT (e, "Failed to switch back down to %s",
2632 gst_element_state_get_name (state));
2635 static GstStateChangeReturn
2636 gst_bin_change_state_func (GstElement * element, GstStateChange transition)
2639 GstStateChangeReturn ret;
2640 GstState current, next;
2641 gboolean have_async;
2642 gboolean have_no_preroll;
2643 GstClockTime base_time, start_time;
2646 GValue data = { 0, };
2648 /* we don't need to take the STATE_LOCK, it is already taken */
2649 current = (GstState) GST_STATE_TRANSITION_CURRENT (transition);
2650 next = (GstState) GST_STATE_TRANSITION_NEXT (transition);
2652 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
2653 "changing state of children from %s to %s",
2654 gst_element_state_get_name (current), gst_element_state_get_name (next));
2656 bin = GST_BIN_CAST (element);
2659 case GST_STATE_PLAYING:
2661 gboolean toplevel, asynchandling;
2663 GST_OBJECT_LOCK (bin);
2664 toplevel = BIN_IS_TOPLEVEL (bin);
2665 asynchandling = bin->priv->asynchandling;
2666 GST_OBJECT_UNLOCK (bin);
2669 gst_bin_recalculate_latency (bin);
2671 gst_element_post_message (element,
2672 gst_message_new_latency (GST_OBJECT_CAST (element)));
2675 case GST_STATE_PAUSED:
2676 /* Clear EOS list on next PAUSED */
2677 GST_OBJECT_LOCK (bin);
2678 GST_DEBUG_OBJECT (element, "clearing EOS elements");
2679 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
2680 bin->priv->posted_eos = FALSE;
2681 if (current == GST_STATE_READY)
2682 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
2683 GST_OBJECT_UNLOCK (bin);
2684 if (current == GST_STATE_READY)
2685 if (!(gst_bin_src_pads_activate (bin, TRUE)))
2686 goto activate_failure;
2688 case GST_STATE_READY:
2689 /* Clear message list on next READY */
2690 GST_OBJECT_LOCK (bin);
2691 GST_DEBUG_OBJECT (element, "clearing all cached messages");
2692 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
2693 GST_OBJECT_UNLOCK (bin);
2694 /* We might not have reached PAUSED yet due to async errors,
2695 * make sure to always deactivate the pads nonetheless */
2696 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2697 goto activate_failure;
2699 case GST_STATE_NULL:
2700 /* Clear message list on next NULL */
2701 GST_OBJECT_LOCK (bin);
2702 GST_DEBUG_OBJECT (element, "clearing all cached messages");
2703 bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
2704 GST_OBJECT_UNLOCK (bin);
2705 if (current == GST_STATE_READY) {
2706 if (!(gst_bin_src_pads_activate (bin, FALSE)))
2707 goto activate_failure;
2714 /* this flag is used to make the async state changes return immediately. We
2715 * don't want them to interfere with this state change */
2716 GST_OBJECT_LOCK (bin);
2717 bin->polling = TRUE;
2718 GST_OBJECT_UNLOCK (bin);
2720 /* iterate in state change order */
2721 it = gst_bin_iterate_sorted (bin);
2723 /* mark if we've seen an ASYNC element in the bin when we did a state change.
2724 * Note how we don't reset this value when a resync happens, the reason being
2725 * that the async element posted ASYNC_START and we want to post ASYNC_DONE
2726 * even after a resync when the async element is gone */
2730 /* take base_time */
2731 base_time = gst_element_get_base_time (element);
2732 start_time = gst_element_get_start_time (element);
2734 have_no_preroll = FALSE;
2738 switch (gst_iterator_next (it, &data)) {
2739 case GST_ITERATOR_OK:
2743 child = g_value_get_object (&data);
2745 /* set state and base_time now */
2746 ret = gst_bin_element_set_state (bin, child, base_time, start_time,
2750 case GST_STATE_CHANGE_SUCCESS:
2751 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2752 "child '%s' changed state to %d(%s) successfully",
2753 GST_ELEMENT_NAME (child), next,
2754 gst_element_state_get_name (next));
2756 case GST_STATE_CHANGE_ASYNC:
2758 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2759 "child '%s' is changing state asynchronously to %s",
2760 GST_ELEMENT_NAME (child), gst_element_state_get_name (next));
2764 case GST_STATE_CHANGE_FAILURE:{
2767 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2768 "child '%s' failed to go to state %d(%s)",
2769 GST_ELEMENT_NAME (child),
2770 next, gst_element_state_get_name (next));
2772 /* Only fail if the child is still inside
2773 * this bin. It might've been removed already
2774 * because of the error by the bin subclass
2775 * to ignore the error. */
2776 parent = gst_object_get_parent (GST_OBJECT_CAST (child));
2777 if (parent == GST_OBJECT_CAST (element)) {
2778 /* element is still in bin, really error now */
2779 gst_object_unref (parent);
2782 /* child removed from bin, let the resync code redo the state
2784 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2785 "child '%s' was removed from the bin",
2786 GST_ELEMENT_NAME (child));
2789 gst_object_unref (parent);
2793 case GST_STATE_CHANGE_NO_PREROLL:
2794 GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
2795 "child '%s' changed state to %d(%s) successfully without preroll",
2796 GST_ELEMENT_NAME (child), next,
2797 gst_element_state_get_name (next));
2798 have_no_preroll = TRUE;
2801 g_assert_not_reached ();
2804 g_value_reset (&data);
2807 case GST_ITERATOR_RESYNC:
2808 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator doing resync");
2809 gst_iterator_resync (it);
2812 case GST_ITERATOR_DONE:
2813 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element, "iterator done");
2819 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
2820 if (G_UNLIKELY (ret == GST_STATE_CHANGE_FAILURE))
2823 if (have_no_preroll) {
2824 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2825 "we have NO_PREROLL elements %s -> NO_PREROLL",
2826 gst_element_state_change_return_get_name (ret));
2827 ret = GST_STATE_CHANGE_NO_PREROLL;
2828 } else if (have_async) {
2829 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
2830 "we have ASYNC elements %s -> ASYNC",
2831 gst_element_state_change_return_get_name (ret));
2832 ret = GST_STATE_CHANGE_ASYNC;
2836 g_value_unset (&data);
2837 gst_iterator_free (it);
2839 GST_OBJECT_LOCK (bin);
2840 bin->polling = FALSE;
2841 /* it's possible that we did not get ASYNC from the children while the bin is
2842 * simulating ASYNC behaviour by posting an ASYNC_DONE message on the bus with
2843 * itself as the source. In that case we still want to check if the state
2844 * change completed. */
2845 if (ret != GST_STATE_CHANGE_ASYNC && !bin->priv->pending_async_done) {
2846 /* no element returned ASYNC and there are no pending async_done messages,
2847 * we can just complete. */
2848 GST_DEBUG_OBJECT (bin, "no async elements");
2851 /* when we get here an ASYNC element was found */
2852 if (GST_STATE_TARGET (bin) <= GST_STATE_READY) {
2853 /* we ignore ASYNC state changes when we go to READY or NULL */
2854 GST_DEBUG_OBJECT (bin, "target state %s <= READY",
2855 gst_element_state_get_name (GST_STATE_TARGET (bin)));
2859 GST_DEBUG_OBJECT (bin, "check async elements");
2860 /* check if all elements managed to commit their state already */
2861 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
2862 /* nothing found, remove all old ASYNC_DONE messages. This can happen when
2863 * all the elements commited their state while we were doing the state
2864 * change. We will still return ASYNC for consistency but we commit the
2865 * state already so that a _get_state() will return immediately. */
2866 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
2868 GST_DEBUG_OBJECT (bin, "async elements commited");
2869 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, FALSE,
2870 GST_CLOCK_TIME_NONE);
2874 bin->priv->pending_async_done = FALSE;
2875 GST_OBJECT_UNLOCK (bin);
2877 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
2878 "done changing bin's state from %s to %s, now in %s, ret %s",
2879 gst_element_state_get_name (current),
2880 gst_element_state_get_name (next),
2881 gst_element_state_get_name (GST_STATE (element)),
2882 gst_element_state_change_return_get_name (ret));
2889 GST_CAT_WARNING_OBJECT (GST_CAT_STATES, element,
2890 "failure (de)activating src pads");
2891 return GST_STATE_CHANGE_FAILURE;
2896 if (current < next) {
2897 GstIterator *it = gst_bin_iterate_sorted (GST_BIN (element));
2898 GstIteratorResult ret;
2900 GST_DEBUG_OBJECT (element,
2901 "Bin failed to change state, switching children back to %s",
2902 gst_element_state_get_name (current));
2905 gst_iterator_foreach (it, &reset_state, GINT_TO_POINTER (current));
2906 } while (ret == GST_ITERATOR_RESYNC);
2907 gst_iterator_free (it);
2914 * This function is a utility event handler for seek events.
2915 * It will send the event to all sinks or sources and appropriate
2916 * ghost pads depending on the event-direction.
2918 * Applications are free to override this behaviour and
2919 * implement their own seek handler, but this will work for
2920 * pretty much all cases in practice.
2923 gst_bin_send_event (GstElement * element, GstEvent * event)
2925 GstBin *bin = GST_BIN_CAST (element);
2927 gboolean res = TRUE;
2928 gboolean done = FALSE;
2929 GValue data = { 0, };
2931 if (GST_EVENT_IS_DOWNSTREAM (event)) {
2932 iter = gst_bin_iterate_sources (bin);
2933 GST_DEBUG_OBJECT (bin, "Sending %s event to src children",
2934 GST_EVENT_TYPE_NAME (event));
2936 iter = gst_bin_iterate_sinks (bin);
2937 GST_DEBUG_OBJECT (bin, "Sending %s event to sink children",
2938 GST_EVENT_TYPE_NAME (event));
2942 switch (gst_iterator_next (iter, &data)) {
2943 case GST_ITERATOR_OK:
2945 GstElement *child = g_value_get_object (&data);
2947 gst_event_ref (event);
2948 res &= gst_element_send_event (child, event);
2950 GST_LOG_OBJECT (child, "After handling %s event: %d",
2951 GST_EVENT_TYPE_NAME (event), res);
2953 g_value_reset (&data);
2956 case GST_ITERATOR_RESYNC:
2957 gst_iterator_resync (iter);
2960 case GST_ITERATOR_DONE:
2963 case GST_ITERATOR_ERROR:
2964 g_assert_not_reached ();
2968 g_value_unset (&data);
2969 gst_iterator_free (iter);
2971 if (GST_EVENT_IS_DOWNSTREAM (event)) {
2972 iter = gst_element_iterate_sink_pads (GST_ELEMENT (bin));
2973 GST_DEBUG_OBJECT (bin, "Sending %s event to sink pads",
2974 GST_EVENT_TYPE_NAME (event));
2976 iter = gst_element_iterate_src_pads (GST_ELEMENT (bin));
2977 GST_DEBUG_OBJECT (bin, "Sending %s event to src pads",
2978 GST_EVENT_TYPE_NAME (event));
2983 switch (gst_iterator_next (iter, &data)) {
2984 case GST_ITERATOR_OK:
2986 GstPad *pad = g_value_get_object (&data);
2988 gst_event_ref (event);
2989 res &= gst_pad_send_event (pad, event);
2990 GST_LOG_OBJECT (pad, "After handling %s event: %d",
2991 GST_EVENT_TYPE_NAME (event), res);
2994 case GST_ITERATOR_RESYNC:
2995 gst_iterator_resync (iter);
2998 case GST_ITERATOR_DONE:
3001 case GST_ITERATOR_ERROR:
3002 g_assert_not_reached ();
3007 g_value_unset (&data);
3008 gst_iterator_free (iter);
3009 gst_event_unref (event);
3014 /* this is the function called by the threadpool. When async elements commit
3015 * their state, this function will attempt to bring the bin to the next state.
3018 gst_bin_continue_func (GstBin * bin, BinContinueData * data)
3020 GstState current, next, pending;
3021 GstStateChange transition;
3023 pending = data->pending;
3025 GST_DEBUG_OBJECT (bin, "waiting for state lock");
3026 GST_STATE_LOCK (bin);
3028 GST_DEBUG_OBJECT (bin, "doing state continue");
3029 GST_OBJECT_LOCK (bin);
3031 /* if a new state change happened after this thread was scheduled, we return
3033 if (data->cookie != GST_ELEMENT_CAST (bin)->state_cookie)
3036 current = GST_STATE (bin);
3037 next = GST_STATE_GET_NEXT (current, pending);
3038 transition = (GstStateChange) GST_STATE_TRANSITION (current, next);
3040 GST_STATE_NEXT (bin) = next;
3041 GST_STATE_PENDING (bin) = pending;
3043 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3044 GST_OBJECT_UNLOCK (bin);
3046 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3047 "continue state change %s to %s, final %s",
3048 gst_element_state_get_name (current),
3049 gst_element_state_get_name (next), gst_element_state_get_name (pending));
3051 gst_element_change_state (GST_ELEMENT_CAST (bin), transition);
3053 GST_STATE_UNLOCK (bin);
3054 GST_DEBUG_OBJECT (bin, "state continue done");
3060 GST_OBJECT_UNLOCK (bin);
3061 GST_STATE_UNLOCK (bin);
3062 GST_DEBUG_OBJECT (bin, "state continue aborted due to intervening change");
3067 static GstBusSyncReply
3068 bin_bus_handler (GstBus * bus, GstMessage * message, GstBin * bin)
3070 GstBinClass *bclass;
3072 bclass = GST_BIN_GET_CLASS (bin);
3073 if (bclass->handle_message)
3074 bclass->handle_message (bin, message);
3076 gst_message_unref (message);
3078 return GST_BUS_DROP;
3082 free_bin_continue_data (BinContinueData * data)
3084 g_slice_free (BinContinueData, data);
3088 bin_push_state_continue (GstBin * bin, BinContinueData * data)
3090 GST_DEBUG_OBJECT (bin, "pushing continue on thread pool");
3091 gst_element_call_async (GST_ELEMENT_CAST (bin),
3092 (GstElementCallAsyncFunc) gst_bin_continue_func, data,
3093 (GDestroyNotify) free_bin_continue_data);
3096 /* an element started an async state change, if we were not busy with a state
3097 * change, we perform a lost state.
3098 * This function is called with the OBJECT lock.
3101 bin_handle_async_start (GstBin * bin)
3103 GstState old_state, new_state;
3105 GstMessage *amessage = NULL;
3107 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
3110 /* get our toplevel state */
3111 toplevel = BIN_IS_TOPLEVEL (bin);
3113 /* prepare an ASYNC_START message, we always post the start message even if we
3114 * are busy with a state change or when we are NO_PREROLL. */
3116 /* non toplevel bin, prepare async-start for the parent */
3117 amessage = gst_message_new_async_start (GST_OBJECT_CAST (bin));
3119 if (bin->polling || GST_STATE_PENDING (bin) != GST_STATE_VOID_PENDING)
3122 /* async starts are ignored when we are NO_PREROLL */
3123 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_NO_PREROLL)
3124 goto was_no_preroll;
3126 old_state = GST_STATE (bin);
3128 /* when we PLAYING we go back to PAUSED, when preroll happens, we go back to
3129 * PLAYING after optionally redistributing the base_time. */
3130 if (old_state > GST_STATE_PAUSED)
3131 new_state = GST_STATE_PAUSED;
3133 new_state = old_state;
3135 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
3136 "lost state of %s, new %s", gst_element_state_get_name (old_state),
3137 gst_element_state_get_name (new_state));
3139 GST_STATE (bin) = new_state;
3140 GST_STATE_NEXT (bin) = new_state;
3141 GST_STATE_PENDING (bin) = new_state;
3142 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3143 GST_OBJECT_UNLOCK (bin);
3146 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), new_state, new_state,
3151 /* post our ASYNC_START. */
3152 GST_DEBUG_OBJECT (bin, "posting ASYNC_START to parent");
3153 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
3155 GST_OBJECT_LOCK (bin);
3161 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3166 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3167 GST_OBJECT_UNLOCK (bin);
3172 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "ignoring, we are NO_PREROLL");
3173 GST_OBJECT_UNLOCK (bin);
3178 /* this function is called when there are no more async elements in the bin. We
3179 * post a state changed message and an ASYNC_DONE message.
3180 * This function is called with the OBJECT lock.
3183 bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
3184 gboolean flag_pending, GstClockTime running_time)
3186 GstState current, pending, target;
3187 GstStateChangeReturn old_ret;
3188 GstState old_state, old_next;
3189 gboolean toplevel, state_changed = FALSE;
3190 GstMessage *amessage = NULL;
3191 BinContinueData *cont = NULL;
3193 if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
3196 pending = GST_STATE_PENDING (bin);
3201 /* check if there is something to commit */
3202 if (pending == GST_STATE_VOID_PENDING)
3203 goto nothing_pending;
3205 old_ret = GST_STATE_RETURN (bin);
3206 GST_STATE_RETURN (bin) = ret;
3208 /* move to the next target state */
3209 target = GST_STATE_TARGET (bin);
3210 pending = GST_STATE_PENDING (bin) = target;
3212 amessage = gst_message_new_async_done (GST_OBJECT_CAST (bin), running_time);
3214 old_state = GST_STATE (bin);
3215 /* this is the state we should go to next */
3216 old_next = GST_STATE_NEXT (bin);
3218 if (old_next != GST_STATE_PLAYING) {
3219 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3220 "committing state from %s to %s, old pending %s",
3221 gst_element_state_get_name (old_state),
3222 gst_element_state_get_name (old_next),
3223 gst_element_state_get_name (pending));
3225 /* update current state */
3226 current = GST_STATE (bin) = old_next;
3228 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3229 "setting state from %s to %s, pending %s",
3230 gst_element_state_get_name (old_state),
3231 gst_element_state_get_name (old_state),
3232 gst_element_state_get_name (pending));
3233 current = old_state;
3236 /* get our toplevel state */
3237 toplevel = BIN_IS_TOPLEVEL (bin);
3239 /* see if we reached the final state. If we are not toplevel, we also have to
3240 * stop here, the parent will continue our state. */
3241 if ((pending == current) || !toplevel) {
3242 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3243 "completed state change, pending VOID");
3245 /* mark VOID pending */
3246 pending = GST_STATE_VOID_PENDING;
3247 GST_STATE_PENDING (bin) = pending;
3248 GST_STATE_NEXT (bin) = GST_STATE_VOID_PENDING;
3250 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
3251 "continue state change, pending %s",
3252 gst_element_state_get_name (pending));
3254 cont = g_slice_new (BinContinueData);
3256 /* cookie to detect concurrent state change */
3257 cont->cookie = GST_ELEMENT_CAST (bin)->state_cookie;
3258 /* pending target state */
3259 cont->pending = pending;
3261 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
3262 GST_STATE_NEXT (bin) = GST_STATE_GET_NEXT (old_state, pending);
3265 if (old_next != GST_STATE_PLAYING) {
3266 if (old_state != old_next || old_ret == GST_STATE_CHANGE_ASYNC) {
3267 state_changed = TRUE;
3270 GST_OBJECT_UNLOCK (bin);
3272 if (state_changed) {
3273 _priv_gst_element_state_changed (GST_ELEMENT_CAST (bin), old_state,
3277 /* post our combined ASYNC_DONE when all is ASYNC_DONE. */
3278 GST_DEBUG_OBJECT (bin, "posting ASYNC_DONE to parent");
3279 gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
3282 GST_OBJECT_LOCK (bin);
3284 /* toplevel, start continue state */
3285 GST_DEBUG_OBJECT (bin, "all async-done, starting state continue");
3286 bin_push_state_continue (bin, cont);
3288 GST_DEBUG_OBJECT (bin, "state change complete");
3289 GST_STATE_BROADCAST (bin);
3295 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
3300 GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
3301 /* if we were busy with a state change and we are requested to flag a
3302 * pending async done, we do so here */
3304 bin->priv->pending_async_done = TRUE;
3309 GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin, "nothing pending");
3315 bin_do_eos (GstBin * bin)
3320 GST_OBJECT_LOCK (bin);
3321 /* If all sinks are EOS, we're in PLAYING and no state change is pending
3322 * we forward the EOS message to the parent bin or application
3324 eos = GST_STATE (bin) == GST_STATE_PLAYING
3325 && GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING
3326 && bin->priv->posted_playing && is_eos (bin, &seqnum);
3327 GST_OBJECT_UNLOCK (bin);
3330 && g_atomic_int_compare_and_exchange (&bin->priv->posted_eos, FALSE,
3332 GstMessage *tmessage;
3334 /* Clear out any further messages, and reset posted_eos so we can
3335 detect any new EOS that happens (eg, after a seek). Since all
3336 sinks have now posted an EOS, there will be no further EOS events
3337 seen unless there is a new logical EOS */
3338 GST_OBJECT_LOCK (bin);
3339 bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
3340 bin->priv->posted_eos = FALSE;
3341 GST_OBJECT_UNLOCK (bin);
3343 tmessage = gst_message_new_eos (GST_OBJECT_CAST (bin));
3344 gst_message_set_seqnum (tmessage, seqnum);
3345 GST_DEBUG_OBJECT (bin,
3346 "all sinks posted EOS, posting seqnum #%" G_GUINT32_FORMAT, seqnum);
3347 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3352 bin_do_stream_start (GstBin * bin)
3355 gboolean stream_start;
3356 gboolean have_group_id = FALSE;
3359 GST_OBJECT_LOCK (bin);
3360 /* If all sinks are STREAM_START we forward the STREAM_START message
3361 * to the parent bin or application
3363 stream_start = is_stream_start (bin, &seqnum, &have_group_id, &group_id);
3364 GST_OBJECT_UNLOCK (bin);
3367 GstMessage *tmessage;
3369 GST_OBJECT_LOCK (bin);
3370 bin_remove_messages (bin, NULL, GST_MESSAGE_STREAM_START);
3371 GST_OBJECT_UNLOCK (bin);
3373 tmessage = gst_message_new_stream_start (GST_OBJECT_CAST (bin));
3374 gst_message_set_seqnum (tmessage, seqnum);
3376 gst_message_set_group_id (tmessage, group_id);
3378 GST_DEBUG_OBJECT (bin,
3379 "all sinks posted STREAM_START, posting seqnum #%" G_GUINT32_FORMAT,
3381 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3385 /* must be called without the object lock as it posts messages */
3387 bin_do_message_forward (GstBin * bin, GstMessage * message)
3389 if (bin->priv->message_forward) {
3390 GstMessage *forwarded;
3392 GST_DEBUG_OBJECT (bin, "pass %s message upward",
3393 GST_MESSAGE_TYPE_NAME (message));
3395 /* we need to convert these messages to element messages so that our parent
3396 * bin can easily ignore them and so that the application can easily
3397 * distinguish between the internally forwarded and the real messages. */
3398 forwarded = gst_message_new_element (GST_OBJECT_CAST (bin),
3399 gst_structure_new ("GstBinForwarded",
3400 "message", GST_TYPE_MESSAGE, message, NULL));
3402 gst_element_post_message (GST_ELEMENT_CAST (bin), forwarded);
3407 gst_bin_update_context (GstBin * bin, GstContext * context)
3409 GST_OBJECT_LOCK (bin);
3410 gst_bin_update_context_unlocked (bin, context);
3411 GST_OBJECT_UNLOCK (bin);
3415 gst_bin_update_context_unlocked (GstBin * bin, GstContext * context)
3417 const gchar *context_type;
3418 GList *l, **contexts;
3420 contexts = &GST_ELEMENT_CAST (bin)->contexts;
3421 context_type = gst_context_get_context_type (context);
3423 GST_DEBUG_OBJECT (bin, "set context %p %" GST_PTR_FORMAT, context,
3424 gst_context_get_structure (context));
3425 for (l = *contexts; l; l = l->next) {
3426 GstContext *tmp = l->data;
3427 const gchar *tmp_type = gst_context_get_context_type (tmp);
3429 /* Always store newest context but never replace
3430 * a persistent one by a non-persistent one */
3431 if (strcmp (context_type, tmp_type) == 0 &&
3432 (gst_context_is_persistent (context) ||
3433 !gst_context_is_persistent (tmp))) {
3434 gst_context_replace ((GstContext **) & l->data, context);
3438 /* Not found? Add */
3440 *contexts = g_list_prepend (*contexts, gst_context_ref (context));
3444 /* handle child messages:
3446 * This method is called synchronously when a child posts a message on
3449 * GST_MESSAGE_EOS: This message is only posted by sinks
3450 * in the PLAYING state. If all sinks posted the EOS message, post
3453 * GST_MESSAGE_STATE_DIRTY: Deprecated
3455 * GST_MESSAGE_SEGMENT_START: just collect, never forward upwards. If an
3456 * element posts segment_start twice, only the last message is kept.
3458 * GST_MESSAGE_SEGMENT_DONE: replace SEGMENT_START message from same poster
3459 * with the segment_done message. If there are no more segment_start
3460 * messages, post segment_done message upwards.
3462 * GST_MESSAGE_DURATION_CHANGED: clear any cached durations.
3463 * Whenever someone performs a duration query on the bin, we store the
3464 * result so we can answer it quicker the next time. Any element that
3465 * changes its duration marks our cached values invalid.
3466 * This message is also posted upwards. This is currently disabled
3467 * because too many elements don't post DURATION_CHANGED messages when
3468 * the duration changes.
3470 * GST_MESSAGE_CLOCK_LOST: This message is posted by an element when it
3471 * can no longer provide a clock. The default bin behaviour is to
3472 * check if the lost clock was the one provided by the bin. If so and
3473 * we are currently in the PLAYING state, we forward the message to
3475 * This message is also generated when we remove a clock provider from
3476 * a bin. If this message is received by the application, it should
3477 * PAUSE the pipeline and set it back to PLAYING to force a new clock
3478 * and a new base_time distribution.
3480 * GST_MESSAGE_CLOCK_PROVIDE: This message is generated when an element
3481 * can provide a clock. This mostly happens when we add a new clock
3482 * provider to the bin. The default behaviour of the bin is to mark the
3483 * currently selected clock as dirty, which will perform a clock
3484 * recalculation the next time we are asked to provide a clock.
3485 * This message is never sent to the application but is forwarded to
3488 * GST_MESSAGE_ASYNC_START: Create an internal ELEMENT message that stores
3489 * the state of the element and the fact that the element will need a
3490 * new base_time. This message is not forwarded to the application.
3492 * GST_MESSAGE_ASYNC_DONE: Find the internal ELEMENT message we kept for the
3493 * element when it posted ASYNC_START. If all elements are done, post a
3494 * ASYNC_DONE message to the parent.
3496 * OTHER: post upwards.
3499 gst_bin_handle_message_func (GstBin * bin, GstMessage * message)
3502 GstMessageType type;
3503 GstMessage *tmessage;
3506 src = GST_MESSAGE_SRC (message);
3507 type = GST_MESSAGE_TYPE (message);
3509 GST_DEBUG_OBJECT (bin, "[msg %p] handling child %s message of type %s",
3510 message, src ? GST_ELEMENT_NAME (src) : "(NULL)",
3511 GST_MESSAGE_TYPE_NAME (message));
3514 case GST_MESSAGE_ERROR:
3516 GST_OBJECT_LOCK (bin);
3518 GST_DEBUG_OBJECT (bin, "got ERROR message, unlocking state change");
3519 GST_STATE_RETURN (bin) = GST_STATE_CHANGE_FAILURE;
3520 GST_STATE_BROADCAST (bin);
3521 GST_OBJECT_UNLOCK (bin);
3525 case GST_MESSAGE_EOS:
3528 /* collect all eos messages from the children */
3529 bin_do_message_forward (bin, message);
3530 GST_OBJECT_LOCK (bin);
3531 /* ref message for future use */
3532 bin_replace_message (bin, message, GST_MESSAGE_EOS);
3533 GST_OBJECT_UNLOCK (bin);
3538 case GST_MESSAGE_STREAM_START:
3541 /* collect all stream_start messages from the children */
3542 GST_OBJECT_LOCK (bin);
3543 /* ref message for future use */
3544 bin_replace_message (bin, message, GST_MESSAGE_STREAM_START);
3545 GST_OBJECT_UNLOCK (bin);
3547 bin_do_stream_start (bin);
3550 case GST_MESSAGE_STATE_DIRTY:
3552 GST_WARNING_OBJECT (bin, "received deprecated STATE_DIRTY message");
3555 gst_message_unref (message);
3558 case GST_MESSAGE_SEGMENT_START:{
3559 gboolean post = FALSE;
3563 gst_message_parse_segment_start (message, &format, &position);
3564 seqnum = gst_message_get_seqnum (message);
3566 bin_do_message_forward (bin, message);
3568 GST_OBJECT_LOCK (bin);
3569 /* if this is the first segment-start, post to parent but not to the
3571 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START) &&
3572 (GST_OBJECT_PARENT (bin) != NULL)) {
3575 /* replace any previous segment_start message from this source
3576 * with the new segment start message */
3577 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3578 GST_OBJECT_UNLOCK (bin);
3580 tmessage = gst_message_new_segment_start (GST_OBJECT_CAST (bin),
3582 gst_message_set_seqnum (tmessage, seqnum);
3584 /* post segment start with initial format and position. */
3585 GST_DEBUG_OBJECT (bin, "posting SEGMENT_START (%u) bus message: %p",
3587 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3591 case GST_MESSAGE_SEGMENT_DONE:
3593 gboolean post = FALSE;
3597 gst_message_parse_segment_done (message, &format, &position);
3598 seqnum = gst_message_get_seqnum (message);
3600 bin_do_message_forward (bin, message);
3602 GST_OBJECT_LOCK (bin);
3603 bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
3604 /* if there are no more segment_start messages, everybody posted
3605 * a segment_done and we can post one on the bus. */
3607 /* we don't care who still has a pending segment start */
3608 if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START)) {
3611 /* remove all old segment_done messages */
3612 bin_remove_messages (bin, NULL, GST_MESSAGE_SEGMENT_DONE);
3614 GST_OBJECT_UNLOCK (bin);
3616 tmessage = gst_message_new_segment_done (GST_OBJECT_CAST (bin),
3618 gst_message_set_seqnum (tmessage, seqnum);
3620 /* post segment done with latest format and position. */
3621 GST_DEBUG_OBJECT (bin, "posting SEGMENT_DONE (%u) bus message: %p",
3623 gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
3627 case GST_MESSAGE_DURATION_CHANGED:
3629 /* FIXME: remove all cached durations, next time somebody asks
3630 * for duration, we will recalculate. */
3632 GST_OBJECT_LOCK (bin);
3633 bin_remove_messages (bin, NULL, GST_MESSAGE_DURATION_CHANGED);
3634 GST_OBJECT_UNLOCK (bin);
3638 case GST_MESSAGE_CLOCK_LOST:
3640 GstClock **provided_clock_p;
3641 GstElement **clock_provider_p;
3642 gboolean playing, toplevel, provided, forward;
3645 gst_message_parse_clock_lost (message, &clock);
3647 GST_OBJECT_LOCK (bin);
3648 bin->clock_dirty = TRUE;
3649 /* if we lost the clock that we provided, post to parent but
3650 * only if we are not a top-level bin or PLAYING.
3651 * The reason for this is that applications should be able
3652 * to PAUSE/PLAY if they receive this message without worrying
3653 * about the state of the pipeline. */
3654 provided = (clock == bin->provided_clock);
3655 playing = (GST_STATE (bin) == GST_STATE_PLAYING);
3656 toplevel = GST_OBJECT_PARENT (bin) == NULL;
3657 forward = provided && (playing || !toplevel);
3659 GST_DEBUG_OBJECT (bin,
3660 "Lost clock %" GST_PTR_FORMAT " provided by %" GST_PTR_FORMAT,
3661 bin->provided_clock, bin->clock_provider);
3662 provided_clock_p = &bin->provided_clock;
3663 clock_provider_p = &bin->clock_provider;
3664 gst_object_replace ((GstObject **) provided_clock_p, NULL);
3665 gst_object_replace ((GstObject **) clock_provider_p, NULL);
3667 GST_DEBUG_OBJECT (bin, "provided %d, playing %d, forward %d",
3668 provided, playing, forward);
3669 GST_OBJECT_UNLOCK (bin);
3675 gst_message_unref (message);
3678 case GST_MESSAGE_CLOCK_PROVIDE:
3682 GST_OBJECT_LOCK (bin);
3683 bin->clock_dirty = TRUE;
3684 /* a new clock is available, post to parent but not
3685 * to the application */
3686 forward = GST_OBJECT_PARENT (bin) != NULL;
3687 GST_OBJECT_UNLOCK (bin);
3693 gst_message_unref (message);
3696 case GST_MESSAGE_ASYNC_START:
3700 GST_DEBUG_OBJECT (bin, "ASYNC_START message %p, %s", message,
3701 src ? GST_OBJECT_NAME (src) : "(NULL)");
3703 bin_do_message_forward (bin, message);
3705 GST_OBJECT_LOCK (bin);
3706 /* we ignore the message if we are going to <= READY */
3707 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3708 goto ignore_start_message;
3710 /* takes ownership of the message */
3711 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3713 bin_handle_async_start (bin);
3714 GST_OBJECT_UNLOCK (bin);
3717 ignore_start_message:
3719 GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
3720 gst_element_state_get_name (target));
3721 GST_OBJECT_UNLOCK (bin);
3722 gst_message_unref (message);
3726 case GST_MESSAGE_ASYNC_DONE:
3728 GstClockTime running_time;
3731 GST_DEBUG_OBJECT (bin, "ASYNC_DONE message %p, %s", message,
3732 src ? GST_OBJECT_NAME (src) : "(NULL)");
3734 gst_message_parse_async_done (message, &running_time);
3736 bin_do_message_forward (bin, message);
3738 GST_OBJECT_LOCK (bin);
3739 /* ignore messages if we are shutting down */
3740 if ((target = GST_STATE_TARGET (bin)) <= GST_STATE_READY)
3741 goto ignore_done_message;
3743 bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
3744 /* if there are no more ASYNC_START messages, everybody posted
3745 * a ASYNC_DONE and we can post one on the bus. When checking, we
3746 * don't care who still has a pending ASYNC_START */
3747 if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
3748 /* nothing found, remove all old ASYNC_DONE messages */
3749 bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
3751 GST_DEBUG_OBJECT (bin, "async elements commited");
3752 /* when we get an async done message when a state change was busy, we
3753 * need to set the pending_done flag so that at the end of the state
3754 * change we can see if we need to verify pending async elements, hence
3755 * the TRUE argument here. */
3756 bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, TRUE,
3759 GST_DEBUG_OBJECT (bin, "there are more async elements pending");
3761 GST_OBJECT_UNLOCK (bin);
3764 ignore_done_message:
3766 GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
3767 gst_element_state_get_name (target));
3768 GST_OBJECT_UNLOCK (bin);
3769 gst_message_unref (message);
3773 case GST_MESSAGE_STRUCTURE_CHANGE:
3777 gst_message_parse_structure_change (message, NULL, NULL, &busy);
3779 GST_OBJECT_LOCK (bin);
3781 /* while the pad is busy, avoid following it when doing state changes.
3782 * Don't update the cookie yet, we will do that after the structure
3783 * change finished and we are ready to inspect the new updated
3785 bin_replace_message (bin, message, GST_MESSAGE_STRUCTURE_CHANGE);
3788 /* a pad link/unlink ended, signal the state change iterator that we
3789 * need to resync by updating the structure_cookie. */
3790 bin_remove_messages (bin, GST_MESSAGE_SRC (message),
3791 GST_MESSAGE_STRUCTURE_CHANGE);
3792 if (!GST_BIN_IS_NO_RESYNC (bin))
3793 bin->priv->structure_cookie++;
3795 GST_OBJECT_UNLOCK (bin);
3798 gst_message_unref (message);
3802 case GST_MESSAGE_NEED_CONTEXT:{
3803 const gchar *context_type;
3804 GList *l, *contexts;
3806 gst_message_parse_context_type (message, &context_type);
3807 GST_OBJECT_LOCK (bin);
3808 contexts = GST_ELEMENT_CAST (bin)->contexts;
3809 GST_LOG_OBJECT (bin, "got need-context message type: %s", context_type);
3810 for (l = contexts; l; l = l->next) {
3811 GstContext *tmp = l->data;
3812 const gchar *tmp_type = gst_context_get_context_type (tmp);
3814 if (strcmp (context_type, tmp_type) == 0) {
3815 gst_element_set_context (GST_ELEMENT (src), l->data);
3819 GST_OBJECT_UNLOCK (bin);
3821 /* Forward if we couldn't answer the message */
3825 gst_message_unref (message);
3830 case GST_MESSAGE_HAVE_CONTEXT:{
3831 GstContext *context;
3833 gst_message_parse_have_context (message, &context);
3834 gst_bin_update_context (bin, context);
3835 gst_context_unref (context);
3847 /* Send all other messages upward */
3848 GST_DEBUG_OBJECT (bin, "posting message upward");
3849 gst_element_post_message (GST_ELEMENT_CAST (bin), message);
3854 /* generic struct passed to all query fold methods */
3863 typedef void (*QueryInitFunction) (GstBin * bin, QueryFold * fold);
3864 typedef void (*QueryDoneFunction) (GstBin * bin, QueryFold * fold);
3866 /* for duration/position we collect all durations/positions and take
3867 * the MAX of all valid results */
3869 bin_query_min_max_init (GstBin * bin, QueryFold * fold)
3877 bin_query_duration_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3879 gboolean res = FALSE;
3880 GstObject *item = g_value_get_object (vitem);
3881 if (GST_IS_PAD (item))
3882 res = gst_pad_query (GST_PAD (item), fold->query);
3884 res = gst_element_query (GST_ELEMENT (item), fold->query);
3889 g_value_set_boolean (ret, TRUE);
3891 gst_query_parse_duration (fold->query, NULL, &duration);
3893 GST_DEBUG_OBJECT (item, "got duration %" G_GINT64_FORMAT, duration);
3895 if (duration == -1) {
3896 /* duration query succeeded, but duration is unknown */
3901 if (duration > fold->max)
3902 fold->max = duration;
3909 bin_query_duration_done (GstBin * bin, QueryFold * fold)
3913 gst_query_parse_duration (fold->query, &format, NULL);
3914 /* store max in query result */
3915 gst_query_set_duration (fold->query, format, fold->max);
3917 GST_DEBUG_OBJECT (bin, "max duration %" G_GINT64_FORMAT, fold->max);
3919 /* FIXME: re-implement duration caching */
3922 GST_OBJECT_LOCK (bin);
3923 bin->messages = g_list_prepend (bin->messages,
3924 gst_message_new_duration (GST_OBJECT_CAST (bin), format, fold->max));
3925 GST_OBJECT_UNLOCK (bin);
3930 bin_query_position_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3932 gboolean res = FALSE;
3933 GstObject *item = g_value_get_object (vitem);
3934 if (GST_IS_PAD (item))
3935 res = gst_pad_query (GST_PAD (item), fold->query);
3937 res = gst_element_query (GST_ELEMENT (item), fold->query);
3942 g_value_set_boolean (ret, TRUE);
3944 gst_query_parse_position (fold->query, NULL, &position);
3946 GST_DEBUG_OBJECT (item, "got position %" G_GINT64_FORMAT, position);
3948 if (position > fold->max)
3949 fold->max = position;
3956 bin_query_position_done (GstBin * bin, QueryFold * fold)
3960 gst_query_parse_position (fold->query, &format, NULL);
3961 /* store max in query result */
3962 gst_query_set_position (fold->query, format, fold->max);
3964 GST_DEBUG_OBJECT (bin, "max position %" G_GINT64_FORMAT, fold->max);
3968 bin_query_latency_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
3970 gboolean res = FALSE;
3971 GstObject *item = g_value_get_object (vitem);
3972 if (GST_IS_PAD (item))
3973 res = gst_pad_query (GST_PAD (item), fold->query);
3975 res = gst_element_query (GST_ELEMENT (item), fold->query);
3977 GstClockTime min, max;
3980 gst_query_parse_latency (fold->query, &live, &min, &max);
3982 GST_DEBUG_OBJECT (item,
3983 "got latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
3984 ", live %d", GST_TIME_ARGS (min), GST_TIME_ARGS (max), live);
3986 /* for the combined latency we collect the MAX of all min latencies and
3987 * the MIN of all max latencies */
3989 if (min > fold->min)
3991 if (fold->max == -1)
3993 else if (max < fold->max)
3999 g_value_set_boolean (ret, FALSE);
4000 GST_DEBUG_OBJECT (item, "failed query");
4007 bin_query_latency_done (GstBin * bin, QueryFold * fold)
4009 /* store max in query result */
4010 gst_query_set_latency (fold->query, fold->live, fold->min, fold->max);
4012 GST_DEBUG_OBJECT (bin,
4013 "latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
4014 ", live %d", GST_TIME_ARGS (fold->min), GST_TIME_ARGS (fold->max),
4018 /* generic fold, return first valid result */
4020 bin_query_generic_fold (const GValue * vitem, GValue * ret, QueryFold * fold)
4022 gboolean res = FALSE;
4023 GstObject *item = g_value_get_object (vitem);
4024 if (GST_IS_PAD (item))
4025 res = gst_pad_query (GST_PAD (item), fold->query);
4027 res = gst_element_query (GST_ELEMENT (item), fold->query);
4029 g_value_set_boolean (ret, TRUE);
4030 GST_DEBUG_OBJECT (item, "answered query %p", fold->query);
4033 /* and stop as soon as we have a valid result */
4037 /* Perform a query iteration for the given bin. The query is stored in
4038 * QueryFold and iter should be either a GstPad iterator or a
4039 * GstElement iterator. */
4041 bin_iterate_fold (GstBin * bin, GstIterator * iter, QueryInitFunction fold_init,
4042 QueryDoneFunction fold_done, GstIteratorFoldFunction fold_func,
4043 QueryFold * fold_data, gboolean default_return)
4045 gboolean res = default_return;
4047 /* set the result of the query to FALSE initially */
4048 g_value_init (&ret, G_TYPE_BOOLEAN);
4049 g_value_set_boolean (&ret, res);
4052 GstIteratorResult ires;
4054 ires = gst_iterator_fold (iter, fold_func, &ret, fold_data);
4057 case GST_ITERATOR_RESYNC:
4058 gst_iterator_resync (iter);
4060 fold_init (bin, fold_data);
4061 g_value_set_boolean (&ret, res);
4063 case GST_ITERATOR_OK:
4064 case GST_ITERATOR_DONE:
4065 res = g_value_get_boolean (&ret);
4066 if (fold_done != NULL && res)
4067 fold_done (bin, fold_data);
4079 gst_bin_query (GstElement * element, GstQuery * query)
4081 GstBin *bin = GST_BIN_CAST (element);
4083 gboolean default_return = FALSE;
4084 gboolean res = FALSE;
4085 gboolean src_pads_query_result = FALSE;
4086 GstIteratorFoldFunction fold_func;
4087 QueryInitFunction fold_init = NULL;
4088 QueryDoneFunction fold_done = NULL;
4089 QueryFold fold_data;
4091 switch (GST_QUERY_TYPE (query)) {
4092 case GST_QUERY_DURATION:
4094 /* FIXME: implement duration caching in GstBin again */
4099 gst_query_parse_duration (query, &qformat, NULL);
4101 /* find cached duration query */
4102 GST_OBJECT_LOCK (bin);
4103 for (cached = bin->messages; cached; cached = g_list_next (cached)) {
4104 GstMessage *message = (GstMessage *) cached->data;
4106 if (GST_MESSAGE_TYPE (message) == GST_MESSAGE_DURATION_CHANGED &&
4107 GST_MESSAGE_SRC (message) == GST_OBJECT_CAST (bin)) {
4111 gst_message_parse_duration (message, &format, &duration);
4113 /* if cached same format, copy duration in query result */
4114 if (format == qformat) {
4115 GST_DEBUG_OBJECT (bin, "return cached duration %" G_GINT64_FORMAT,
4117 GST_OBJECT_UNLOCK (bin);
4119 gst_query_set_duration (query, qformat, duration);
4125 GST_OBJECT_UNLOCK (bin);
4127 GST_FIXME ("implement duration caching in GstBin again");
4129 /* no cached value found, iterate and collect durations */
4130 fold_func = (GstIteratorFoldFunction) bin_query_duration_fold;
4131 fold_init = bin_query_min_max_init;
4132 fold_done = bin_query_duration_done;
4135 case GST_QUERY_POSITION:
4137 fold_func = (GstIteratorFoldFunction) bin_query_position_fold;
4138 fold_init = bin_query_min_max_init;
4139 fold_done = bin_query_position_done;
4142 case GST_QUERY_LATENCY:
4144 fold_func = (GstIteratorFoldFunction) bin_query_latency_fold;
4145 fold_init = bin_query_min_max_init;
4146 fold_done = bin_query_latency_done;
4147 default_return = TRUE;
4151 fold_func = (GstIteratorFoldFunction) bin_query_generic_fold;
4155 fold_data.query = query;
4157 iter = gst_bin_iterate_sinks (bin);
4158 GST_DEBUG_OBJECT (bin, "Sending query %p (type %s) to sink children",
4159 query, GST_QUERY_TYPE_NAME (query));
4162 fold_init (bin, &fold_data);
4165 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func, &fold_data,
4167 gst_iterator_free (iter);
4170 /* Query the source pads of the element */
4171 iter = gst_element_iterate_src_pads (element);
4172 src_pads_query_result =
4173 bin_iterate_fold (bin, iter, fold_init, fold_done, fold_func,
4174 &fold_data, default_return);
4175 gst_iterator_free (iter);
4177 if (src_pads_query_result)
4181 GST_DEBUG_OBJECT (bin, "query %p result %d", query, res);
4187 set_context (const GValue * item, gpointer user_data)
4189 GstElement *element = g_value_get_object (item);
4191 gst_element_set_context (element, user_data);
4195 gst_bin_set_context (GstElement * element, GstContext * context)
4198 GstIterator *children;
4200 g_return_if_fail (GST_IS_BIN (element));
4202 bin = GST_BIN (element);
4204 GST_ELEMENT_CLASS (parent_class)->set_context (element, context);
4206 children = gst_bin_iterate_elements (bin);
4207 while (gst_iterator_foreach (children, set_context,
4208 context) == GST_ITERATOR_RESYNC)
4209 gst_iterator_resync (children);
4210 gst_iterator_free (children);
4214 compare_name (const GValue * velement, const gchar * name)
4217 GstElement *element = g_value_get_object (velement);
4219 GST_OBJECT_LOCK (element);
4220 eq = strcmp (GST_ELEMENT_NAME (element), name);
4221 GST_OBJECT_UNLOCK (element);
4227 * gst_bin_get_by_name:
4229 * @name: the element name to search for
4231 * Gets the element with the given name from a bin. This
4232 * function recurses into child bins.
4234 * Returns %NULL if no element with the given name is found in the bin.
4236 * MT safe. Caller owns returned reference.
4238 * Returns: (transfer full) (nullable): the #GstElement with the given
4242 gst_bin_get_by_name (GstBin * bin, const gchar * name)
4244 GstIterator *children;
4245 GValue result = { 0, };
4246 GstElement *element;
4249 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4251 GST_CAT_INFO (GST_CAT_PARENTAGE, "[%s]: looking up child element %s",
4252 GST_ELEMENT_NAME (bin), name);
4254 children = gst_bin_iterate_recurse (bin);
4255 found = gst_iterator_find_custom (children,
4256 (GCompareFunc) compare_name, &result, (gpointer) name);
4257 gst_iterator_free (children);
4260 element = g_value_dup_object (&result);
4261 g_value_unset (&result);
4270 * gst_bin_get_by_name_recurse_up:
4272 * @name: the element name to search for
4274 * Gets the element with the given name from this bin. If the
4275 * element is not found, a recursion is performed on the parent bin.
4278 * - no element with the given name is found in the bin
4280 * MT safe. Caller owns returned reference.
4282 * Returns: (transfer full) (nullable): the #GstElement with the given
4286 gst_bin_get_by_name_recurse_up (GstBin * bin, const gchar * name)
4290 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4291 g_return_val_if_fail (name != NULL, NULL);
4293 result = gst_bin_get_by_name (bin, name);
4298 parent = gst_object_get_parent (GST_OBJECT_CAST (bin));
4300 if (GST_IS_BIN (parent)) {
4301 result = gst_bin_get_by_name_recurse_up (GST_BIN_CAST (parent), name);
4303 gst_object_unref (parent);
4311 compare_interface (const GValue * velement, GValue * interface)
4313 GstElement *element = g_value_get_object (velement);
4314 GType interface_type = (GType) g_value_get_pointer (interface);
4317 if (G_TYPE_CHECK_INSTANCE_TYPE (element, interface_type)) {
4326 * gst_bin_get_by_interface:
4328 * @iface: the #GType of an interface
4330 * Looks for an element inside the bin that implements the given
4331 * interface. If such an element is found, it returns the element.
4332 * You can cast this element to the given interface afterwards. If you want
4333 * all elements that implement the interface, use
4334 * gst_bin_iterate_all_by_interface(). This function recurses into child bins.
4336 * MT safe. Caller owns returned reference.
4338 * Returns: (transfer full): A #GstElement inside the bin implementing the interface
4341 gst_bin_get_by_interface (GstBin * bin, GType iface)
4343 GstIterator *children;
4344 GValue result = { 0, };
4345 GstElement *element;
4347 GValue viface = { 0, };
4349 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4350 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4352 g_value_init (&viface, G_TYPE_POINTER);
4353 g_value_set_pointer (&viface, (gpointer) iface);
4355 children = gst_bin_iterate_recurse (bin);
4356 found = gst_iterator_find_custom (children, (GCompareFunc) compare_interface,
4358 gst_iterator_free (children);
4361 element = g_value_dup_object (&result);
4362 g_value_unset (&result);
4366 g_value_unset (&viface);
4372 * gst_bin_iterate_all_by_interface:
4374 * @iface: the #GType of an interface
4376 * Looks for all elements inside the bin that implements the given
4377 * interface. You can safely cast all returned elements to the given interface.
4378 * The function recurses inside child bins. The iterator will yield a series
4379 * of #GstElement that should be unreffed after use.
4381 * MT safe. Caller owns returned value.
4383 * Returns: (transfer full) (nullable): a #GstIterator of #GstElement
4384 * for all elements in the bin implementing the given interface,
4388 gst_bin_iterate_all_by_interface (GstBin * bin, GType iface)
4390 GstIterator *children;
4391 GstIterator *result;
4392 GValue viface = { 0, };
4394 g_return_val_if_fail (GST_IS_BIN (bin), NULL);
4395 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
4397 g_value_init (&viface, G_TYPE_POINTER);
4398 g_value_set_pointer (&viface, (gpointer) iface);
4400 children = gst_bin_iterate_recurse (bin);
4401 result = gst_iterator_filter (children, (GCompareFunc) compare_interface,
4404 g_value_unset (&viface);